361all, 361pt2
What is Spectral Radiant Emittance?
Power emitted per area per wavelength
Apart from location, GPS data can also be used for:
Precise timing and Frequency calibration
Remote sensing includes:
Processing, Recording, and sensing
Electromagnetic radiation:
Produces a time varying magnetic field and vice versa. Once generated, remains self-propagating. Is capable to travel across space. Consists of magnetic and electric fields.
Panchromatic
Produces black and white images
What is the principal objective of an ATSR?
Providing data and information concerning global Sea Surface Temperature (SST)
Which among these can be an active medium of remote sensing?
RADAR
Which can bee an active medium of remote sensing?
RADAR
The output from a thermal sensor is a measurement of the __________ temperature of an object:
Radiant
The radiant energy flow in a given unit volume is called the
Radiant Flux Density
The radiant energy flow per unit volume is
Radiant Flux Density
RADAR is an acronym for:
Radio Detection and Ranging
This is an instrument for detecting or measuring the intensity or force of radiation
Radiometer
Let's say you're taking an image of an area to gather data on the temperature of a forest fire in that area. What resolution do you necessarily need in your scanner?
Radiometric
A pre-processing method to reconstruct physically calibrated values by correcting the spectral errors and distortions caused by sensors is called:
Radiometric correction
A satellite sensor with the ability to sense small energy differences is known to have a high:
Radiometric resolution
Explain the two types of resolutions that remote sensing deals with.
Radiometric resolution is the number of levels that a sensor can record spectral information. Geometric resolution is the smallest amount of area on the Earth's surface for which a sensor can record radiometric information.
This data format is easy to manipulate mathematically and is stored very efficiently, but is limited by spatial resolution
Raster
Which scattering occurs when particles are very small compared to the wavelength of the radiation?
Rayleigh
Which type of scattering is responsible for the red appearance of the sky during sunrise and sunset?
Rayleigh scattering
Name one common Lidar application
Rayleigh scattering, Mie Scattering, Raman scattering, and fluorescense
What is the dominant scattering mechanism in the upper atmosphere?
Rayleigh scattering
What is a RAR?
Real Aperture Radar
Overall shape of an image can only be:
Rectangular and square
A beam of light has a wavelength of 660 nm. What color is this light?
Red
In false colour composite (FCC) image healthy vegetation appears:
Red
What color does living vegetation appear as on false color IR images?
Red
What color do living plants appear as on false-colour infrared images?
Red
Which colour is having largest wavelength in visible spectrum
Red
With the increase of turbidity, the muddy water appears brown due to the shift of the upward radiance peak towards:
Red
energy absorbed by vegetation is highest in __ region and lowest in __ region of the Ems
Red and NIR
Anaglyph 3D images are images which contain two differently filtered color images. Traditionally, thin paper glasses with red and blue color filters were used to view these anaglyphs. The color filters thus cause each eye to view one of the two images in the anaglyph, tricking the brain into perceiving depth (the 3D effect) when the brain reassembles the two images into one. For the red color filter, which of the following is accurate about color perception:
Red through the filter appears white, blue light appears black
What range of colors are used is for the sensing, representation, and display of images in modern electronic systems and photography?
Red, Green, Blue
Which of the following best describes scattering?
Redirection of incoming radiation by particles in the air.
The part radiation due to scattered/diffused radiation entering the field of view of a remote sensor other than that from the required target:
Reduces the contrast of the image and also its sharpness
Which of the following best describes the process of binning?
Reduction of noise
What is the most common source of radiation detected by passive sensors?
Reflected sunlight
Clouds directly affect the Earth's energy balance by
Reflecting incoming sunlight back into space, and Absorbing and emitting reflected light back into space
A type of telescope that uses a mirror is typically called a ___________________ telescope and uses a _______________ mirror.
Reflecting; Concave
Albedo
Reflectivity of a surface
A telescope that uses only lenses for magnification is called a ___________ telescope.
Refracting
Which of the following best describes the phenomenon of light bending as it passes from one medium to another?
Refraction
................. is the technology of acquiring information about the Earth's surface without actually being in contact with it?
Remote Sensing
The size and number of detector elements in a CCD determine the device's:
Resolution
The human eye lens is meant to focus an object's image onto the ______________.
Retina
In electromagnetic radiation, electrical and magnetic fields travel at:
Right angles to each other
_______________ is a measure of the accuracy of an entire geospatial dataset.
Root mean square error
If an image has high backscatter, what does it say about the landscape being imaged?
Rough surface
Ground deformation can be studied using
SAR interferometery
The image-to-world transformation is a ...... -parameter Affine Transformation:
SIX
Which of the following remote sensing technologies use sound?
SONAR
CO2 is mostly absorbed in the __ and __ wavelength regions of the EMS
SWIR and TIR
What is redirection of electromagnetic energy by suspended particles in atmosphere or gas molecules of atmosphere called?
Scattering
Which phenomena occurs when particles or large gas molecules present in the atmosphere interact with and cause the electromagnetic radiation to be redirected from its original path:
Scattering
hich of the following instruments features eight spectral bands?
SeaWiFS
What is meant by the term 'spatial filtering' in remote sensing?
Selectively preserving certain pixel frequencies in an image to enhance particular features or edges of objects
What is meant by the term 'spatial filtering' in remote sensing?
Selectively preserving certain pixel frequencies in an image to enhance particular features or edges of objects
IFOV is angular cone of visibility of the:
Sensor
What does a dichroic grating do in satellite systems?
Separates thermal and nonthermal energy
The ........ the wavelength, the higher the frequency. The ....... the wavelength, the lower the frequency?
Shorter, longer
The ultraviolet part of the spectrum has the ......... wavelengths?
Shortest wavelength
Which one of the following helps to identify the objects on the earth surface?
Signature
Images sometimes appear slightly to the west of each previous scan due to the eastward rotation of the Earth. This is due to:
Skew distortion
Images sometimes appear slightly to the west of each previous scan due to the eastward rotationof the Earth. This is due to:
Skew distortion
What is remote sensing?
Small or large-scale acquisition of information of an object or phenomenon not in physical or intimate contact
How do smooth surfaces appear in a remote sensing image compared to rough surfaces?
Smooth surfaces are darker in color due to specular reflection
___________________ first observed that there is a relationship between the angle of incidence and angle of refraction.
Snell
The reflectance from a surface is called specular reflection if it follows
Snell's law
The reflectance from a surface is called specular reflection if it follows:
Snells's law
What does the CERES instrument measure?
Solar-reflected and Earth-emitted radiation (radiative energy flux)
As the IFOV of a sensor is decreased, the:
Spatial resolution increases
The arrangement of terrain features which provides the shape, size and texture of objects, is called:
Spatial variation
Remote Sensing technology is a:
Spatial, Digital and Generic
Why endmembers are called pure pixels?
Specific for a particular feature
Vegetation can easily be distinguished from other types of land because of its unique ___.
Spectral reflectance signature
The difference in the reflectance/emittance characteristics with respect to wavelengths is called:
Spectral signature
The phenomena in spherical lenses of some light rays missing the focal point is called _____________________.
Spherical Aberration
The optical properties describing the interaction between aerosol and solar radiation must assume that particles are __________ and ____________.
Spherical; homogeneous
What was the first satellite launched in space called?
Sputnik 1
What is the name of the first satellite? Suomi NPP Kalpana-1 CALIPSO Sputnik 1
Sputnik 1
The shape of a pixel of an image can only be:
Square
In aerial photos, the phenomena used to create depth is:
Stereoscopic effect
Blue shift in red-edge of vegetation spectra is indicator of
Stressed vegetation
What is the primary focus of GCOM-W1 "SHIZUKU"?
Studying the water cycle
A passive sensor uses:
Sun as the source of energy
Most of the passive sensors use:
Sun as the source of energy
In general, Remote Sensing satellites orbit in:
Sun-synchronous
NOAA-19 satellite is having AVHRR sensor and orbiting in:
Sun-synchronous
Polar or near polar orbits are also known as?
Sun-synchronous
The A-Train is a system of sitellites in what type of orbit?
Sun-synchronous
Which type of orbit is used by near-polar orbiting remote sensing satellites?
Sun-synchronous orbit
Which describes MODIS instruments?
Superspectral
Remote Sensing is unique because it provides:
Synoptic view
The distinct advantages of remote sensing are?
Synoptic view, Global coverage, Repeatability
Thermal inertia of air temperature is higher than land surface temperature
TRUE
Considering the basic energy balance model equation: Ts = Te + dT What do the three variables in the equation represent?
Te = Effective temperature Ts = Surface temperature dT = the greenhouse increment
Generally, purpose of geostationary satellite is:
Telecommunication and weather monitoring
The changes in the reflectivity/emissivity with time, is called:
Temporal variation
If an image is placed to the left of a converging lens, which of the following statements are true?
The image can be upright or inverted
For much of the electromagnetic spectrum, earth's atmosphere acts as a barrier which absorbs most wavelengths in the ultraviolet range and shorter. For longer radio waves, the ionosphere may act as a reflector as shown below. Based on the following diagram and the information above, select the most accurate statement:
The ionosphere reflects specularly with great efficiency, and The atmosphere will absorb visible light
Which statement best characterizes specular and diffuse reflection?
The law of reflection applies to both diffuse and specular surfaces.
What is meant by the term 'precision'?
The level of detail at which data is stored
What happens to visible light rays, at some given frequency, that are absorbed by an object?
The light waves are converted to thermal energy.
In which part of the reflective optical infrared region, the effect of multiple leaves in vegetation canopy is maximum?
The near-IR (0.7 - 1.3 μm) region
Which one is appropriate definition of scale?
The ratio of a distance on a map to the corresponding distance on the ground
Resolution may best be defined as:
The smallest feature that can be mapped or measured
A passive sensor detects light reflected or hansmitted from which of the following sources?
The sun and cities (i.e. electric lights)
There are two Survey of India 1:50,000 toposheets with 15' X 15' angular coverage, one from Jammu and another from Kerala. Which of the following statement is true?
The toposheet from Kerala will cover a larger area than that of the Jammu
No surface is perfectly smooth. What wave feature must be similar to or greater that the irregularities on a surface in order to achieve specular reflection?
The wavelength
Scattering depends on several factors including:
The wavelength of the radiation, The abundance of particles or gases, and The distance the radiation travels through the atmosphere
Where is the atmospheric refraction for a star the lowest?
The zenith, or highest point above the earth
For measuring SST, name two advantages of using either passive microwave radiation or thermal IR over the other.
Thermal IR advantages -better resolution, record goes further back, insensitive to surface roughness and precipitation, offer surface or skin profile of SST (radiation does not travel far below ocean surface) Microwave advantages -microwave radiation penetrates cloud cover/insensitive to cloud cover, better coverage, microwave penetrates farther below the sea surface, insensitive to atmospheric effects, offer bulk profile of SST (radiation travels farther below ocean surfaces)
The observation that water has roughly uniform surface temperatures throughout the day andnight means that water has a high:
Thermal inertia
Which of the following might be considered as the fourth dimension in Remote Sensing?
Time
Temporal Resolution
Time between two images of the same area
Ratio transformations can be used to reduce the effects of:
Topography
_______ generally refers to the spatial arrangement among geographic objects and may be managed within a geographic information system through the application of rules such as "Adjacent to" or "May not have gaps".
Topology
GPS is based on a principle called:
Trilateration
Global Positioning Service (GPS) is based on a principle called:
Trilateration
All of the planet's weather takes place in the
Troposphere
Push broom sensors scan the surface in the direction parallel to the motion of the satellite
True
T/F: Active sensors have their own energy source.
True
True or False: Principal Component Analysis is the analysis of data to identify and find patterns to reduce the dimensions of a dataset with minimal loss of information.
True
What is passive sensing?
Where information is recorded just from the sunlight bouncing off objects.
What is active sensing?
Where the satellite or aircraft produces or beams a signal towards the object or land.
Which of the following is the definition of 'parallax'?
The apparent change in position of an object when viewed from two different positions
What is the primary reason that short-wavelength radiation is unsuitable for remote sensing?
The atmosphere absorbs it
What is meant by the term 'accuracy'?
The extent to which a value approaches its true value
The value of energy quantum for radiation of any frequency is proportional to:
The frequency
Light with wavelengths from 525 to 550 nm will be detected by which cone(s) in the retina?
The green and red cones
Describe Wien's law?
Wien's displacement law states that the black body radiation curves for different temperatures peaks at a wavelength inversely proportional to the temperature.
There are areas of the EM spectrum where the atmosphere is transparent to specific wavelengths. These wavelength bands are known as atmospheric ___, since they allow the energy to easily pass through the atmosphere to Earth's surface.
Windows
What is the unit of radiative forcing?
Wm ^-2 (i.e. W/m^2)
The __ band of the microwave region is useful for observations in adverse weather conditions
X
Can oil spills be detected by LandSat imagery?
Yes, large enough ones can be detected with Landsat
What is false color?
a coloring technique used to highlight particular features of photographs
Which of the following two plants has a higher reflectance for its spectral response curve? a. Conifer b. Deciduous
a. Conifer
Electromagnetic waves are defined to behave in the same way of which of the following waves?
a. Transverse waves
Which of the following is NOT an active sensor? a. accelerometer b. RADAR c. LiDAR d. Laser Altimeter
a. accelerometer
Healthy vegetation will ___ most of the visible light falling on it:
absorb
attenuates reflected radiance
absorption
carbon dioxide, ozone and water vapor are primarily responsible for this effect
absorption
What helps to identify a particular feature in case of band ratios from a spectral curve?
absorption and reflection peaks
What is the difference between "whiskbroom" and "pushbroom" scanning?
across-track vs. along track
Which type of sensors provide their own energy source for illumination:
active
The interaction of the electromagnetic radiation produced with a specific wave length to illuminate a target on the terrain for studying its scattered radiance, is called
active remote sensing
The interaction of the electromagnetic radiation produced with a specific wave length to illuminate a target on the terrain for studying its scattered radiance, is called:
active remote sensing
A(n)_______________ is a radar instrument used for measuring signals transmitted by the sensor that were reflected, refracted or scattered by the Earth's surface or its atmosphere.
active sensor
The instruments which provide electromagnetic radiation of specified wave length or a band of wave lengths to illuminate the earth surface, are called
active sensors
In the atmosphere, tiny solid or liquid suspended particles of various composition are called
aerosols
A beam of light travels fastest in
air
The ratio of the total solar radiant energy returned by a planetary body to the total radiant energy incident on the body, the called
albedo
Which science question(s) does the Aura mission seek to answer? Choose all that apply. Is the stratospheric ozone layer recovering? What are the processes controlling air quality? How is Earth's climate changing? How is the global Earth system changing?
all
Supervised classification technique is based on? -Minimum distance to means classification (Chain Method) algorithm -Gaussian Maximum likelihood algorithm -Parallelpiped algorithm -All of the above
all of the above
The optical property of water depends on: a) absorption by the dissolved material b) absorption by the suspended particulate matter c) scattering by the suspended particulate matter d) all of the above
all of the above
Due to scan geometry of a satellite sensor: -The off-nadir resolution is degraded -The ground distance swept by the senor, IFOV is proportional to sec2θ, where θ is the angle of scan measured from the nadir -The details towards the edge of the scan get compressed -All of these
all of these
Pick the correct statement: a) When the electric field oscillates in the direction of the electric vector, a plane polarized wave is formed b) When the electric vector is in the plane of incidence, vertical polarization is formed c) When the electric vector is at right angles to the plane of incidence, horizontal polarization wave is formed d) the plane containing then incident ray and normal to the reflecting surface at the point of incidence is called the plane of incidence
all of these
Which one of the following parameters is considered to determine the reflectance of a vegetation canopy? A. Solar zenith angle B. Azimuth angleC. Look angleD. All of these
all of these
If you know the wavelength of any form of electromagnetic radiation, you can determine its frequency because
all wavelengths travel at the same speed.
In case of reflection and refraction of electromagnetic radiation,
angle of incidence = angle of reflection
The amount of heat radiated by a surface is proportional to the fourth power of its temperature. This means:
as earth's temperature rises, an increasing proportion of heat is radiated into space
Which of the following is ordered from lowest to highest albedo? new concrete, water, conifer forests asphalt, woodlands, grasslands snow, desert, moon deciduous trees, ocean ice, soil
asphalt, woodlands, grasslands
Dhadows in a satellite image often _____ to calculate height of an object.
assist
AOT leads to __ error
atmospheric
The spectral region of the electromagnetic radiation which passes through the atmosphere without much attenuation is known a
atmospheric window
A beam of light emerges from water into air at an angle. The beam is bent
away from the normal.
In order of increasing frequency, which of the following is correct? a. visible, radio, ultraviolet and x‐ray b. infrared, visible, ultraviolet and gamma c. visible, gamma, ultraviolet and x‐ray d. infrared, x‐ray, visible and gamma
b. infrared, visible, ultraviolet and gamma
Which statement is inconsistent with passive sensing scanning systems? a. Passive sensing systems require an external radiation source b. Passive sensing involves pushbroom scanning c. SAR is not a type of passive sensing d. All of the Above e. None of the Above
b. Passive sensing involves pushbroom scanning
When a light ray passes at an angle to the normal from one material into another material in which its speed is lower, the ray [___].
bends toward the normal to the surface
Wein's law
black body radiation curves peak at a wavelength inversely proportional to the temperature
An object that absorbs all radiation falling on it, at all wavelengths, is called a(n) _________________.
blackbody
What is yellow's complimentary color?
blue
Which one of the following statements regarding remote sensing is correct: (a) The interaction of the electromagnetic radiation with the target (b) The emission of electromagnetic radiation from the target (c) both (a) and (b) (d) Neither (a) nor (b)
both (a) and (b)
Affects visible and near infrared regions
both absorption and scattering
Wavelength 1 cm - 100cm encompasses which forms of remote sensing?
both active and passive
pixels in a typical remote sensing image represent __ of a part of the Earth:
brightness/ emissivity
Identify the incorrect statement. a. A perfect blackbody absorbs all incident radiation without reflecting any b. To stay in thermal equilibrium, a blackbody must emit radiation at the same rate that it absorbs it c. A blackbody at a uniform temperature displays a characteristic frequency distribution that depends upon its density d. Black holes are near-perfect blackbodies e. Simple models of planetary energy balance approximate a planet as a perfect blackbody
c
Which of the following is not monitoring the atmosphere as part of EOS? a. ICESat b. Terra c. ROCSat d. SORCE
c. ROCSat
Which of the following choices shows the correct order of decreasing wavelength from the electromagnetic spectrum? a. Microwave, UV, Infrared, Visible, Radio b. Radio, Microwave, UV, Visible, Infrared c. Radio, Microwave, Infrared, Visible, UV d. Infrared, Microwave, Radio, UV, Visible None of the above
c. Radio, Microwave, Infrared, Visible, UV
Given the following statement about optical instruments, select the statement that is incorrect: a) For a simple compound microscope, the second focal point f2 of the objective is separated from the first focal point f1' of the eyepiece. b)For a simple refractive telescope, the second focal point f2 of the objective coincides in position with the first focal point f1' of the eyepiece c)Refracting telescopes avoid the problem of chromatic and spherical aberration that plague reflecting telescopes d)For a simple compound microscope, the final virtual image I' forms almost at an infinite distance away from the microscope e)A magnifying glass is considered to be a simple magnifier
c. Refracting telescopes avoid the problem of chromatic and spherical aberration that plague reflecting telescopes
Which of the types of waves below has the longest wavelength? a. X-rays b. Gamma Rays c. Radio Waves d. Near Infrared Waves
c. radio waves
Which of the following best describes the image from a plane mirror? a. virtual and magnification greater than one b. real and magnification less than one c. virtual and magnification equal to one d. real and magnification equal to one
c. virtual and magnification equal to one
Wavelength and frequency are related by the following formula:
c=λν
A penny lies in the bottom of a tea cup filled with water. As you look down on the penny, compared to its actual depth, it looks
closer.
Interferometric SAR (InSAR), allows accurate measurements of the radiation travel path because it is:
coherent
The spectrum produced by a prism or a raindrop is evidence that the average speed of light in the material depends on the light's
color
What is the advantage of absolute atmospheric correction over relative?
comparison over space and time, comparison between inset and satellite measurements, less approximation
Digital image processing is the use of _____ to perform image processing on digital images:
computer algorithms
Moon's surface is marked by large number of:
craters
Which intensity interpolation technique among these, adopts maximum approximation for assigning resampled value to a pixel?
cubic convolution
Which of the following is NOT a reason why remote sensing is ideal for use in Natural Sciences? a) it can be applied at any scale b) it can monitor change over time c) it minimizes the need for fieldwork in dangerous, isolated and sensitive areas d) It will always be more reliable than fieldwork studies
d) It will always be more reliable than fieldwork studies
Spectral resolution of an image is defined by considering the a) central wavelength b) band widths c) number of bands d) all of the above
d) all of the above
What is the drawback of using passive sensors? a) not useful in all weather conditions b) cannot be used for all times of the day c) is not very useful at night d) all of the above
d) all of the above
Pick the correct statement: a) phase of a wave is expressed as a fraction of a period with respect to a reference b) phase is usually specified by angular measure with one period being 360 degrees c) the reference for finding the phase of a wave is taken from the previous passage through zero from the negative to the positive direction d) all of these
d) all of these
The basic requirement for any sensor system is: a) radiometric resolution b) spatial resolution c) spectral resolution d) all of these
d) all of these
Which one of these statements is correct? a) during the day, earth reflects solar radiation b) during the day, earth reflects both solar radiation the emission from its surface c) during the night, earth emits radiation from its surface d) all of these
d) all of these
Which of the following errors is produced by platform characteristics of the sensor? a) missing scan lines b) radiometric c) skewness d) none of the above
d) none of the above
Remote sensing can not measure which of the following? a. Ocean floor topography b. Water temperature c. Wind speed and direction above d. none of the above
d. none of the above
Which of the following type of waves have the longest wavelength?a. X-rays b. hertzian waves c.gamma waves d. radio waves e. near infrared waves
d. radio waves
In a file with .dbf extension, what does the .dbf stand for?
database file
plank's law
describes black body spectral radiance as a function of its wavelength at a given temperature
Light goes from Medium A to Medium B at an angle of incidence of 40°, the angle of refraction is 30°. The velocity of light in Medium B is:
less than in A
Which of the following types of sensors uses a highly focused beam of light?
lidar
most passive microwave sensors are therefore characterized by:
low spatial resolution
A digital image is a numeric representation of a two-dimensional:
matrix
How does a whiskbroom scanner differ from a pushbroom scanner?
mirror moves back and forth
what type of satellite data will be most suitable for ocean monitoring considering all resolutions combined?
moderate resolution
The SAR interferogram is generated by cross- ____, pixel by pixel, the first SAR image with the complex conjugate of the second:
multiplying
In hyperspectral remote sensing, generally bands are relatively ___ as compared to multispectral remote sensing:
narrow
You can hear noises a long distance away over water at night because
of refraction of sound in air.
Measures natural emissions produced by Earth's surface and atmosphere.
passive
Which radiation type does the ASMR-e satellite use?
passive microwave
A(n) _____________________ is a microwave instrument designed to receive and to measure natural emissions produced by constituents of the Earth's surface and its atmosphere.
passive sensor
Refraction is caused by
different wave speeds.
If the wavelengths are much smaller than the surface variations or the particle sizes that make up the surface_____ reflection will dominate
diffuse
Snow reflects almost all of the light incident upon it. However, a single beam of light is not reflected in the form of parallel rays. This is an example of ____ reflection off of a ____ surface.
diffuse; rough
Black body
perfectly efficient absorption of electromagnetic radiation
The distance between the two satellites (or orbits) in the plane perpendicular to the orbit is called the interferometer baseline and its projection perpendicular to the slant range is the:
perpendicular baseline
Raster images have a finite set of digital values, called:
pixels
All bodies at temperatures above absolute zero degree emit electromagnetic radiation at different wave length", is known as:
planks law
Image can have only ___ integer pixel values, whereas grid can have __ and __ real and __ cell values
positive, positive, negative, integer
CMYK colour scheme is used for:
printing
Stars twinkle when seen from Earth at night. When seen from the moon, stars
don't twinkle
electromagnetic radiation: a) produces a time varying magnetic field and vice versa B)once generated, remains self-propagating c)is capable to travel across space d) consists of magnetic and electric fields e)all of the above
e) all of the above
Identify the correct statement from the following: a) the distance between two successive crests or troughs of a wave, is called, the wave length b)the wave length is measured in meters and a fraction of a meter c) the wave length his generally denoted by /\ d) the length of the crest from the midpoint, is called amplitude e) all of these
e) all of these
Which of these is a disadvantage of remote sensing as a tool? a. Difficulties with image interpretation b. Coarse Resolution c. Uncertainty and distortion with measurements d. Two of the Above e. All of the Above
e. All of the Above
radiation that is not absorbed or scattered in the atmosphere can reach and interact with the:
earth's surface
emissivity
effectiveness of a surface in emitting thermal radiation
Remote sensing techniques makes use of the properties of-----emitted, reflected or diffracted by the sensed objects:
electromagnetic waves
Pixels are the smallest individual __ of an image
element, unit, component
The Stefan-Boltzmann law states that the total radiant heat energy ______________ from a surface is proportional to the __________ power of its absolute temperature. ... The law applies only to blackbodies, theoretical surfaces that ___________ all incident heat radiation.
emitted; fourth; absorb
Stefan-boltzmann law
energy radiated by a black body is proportional to the fourth power of the black body's temperature
what is the significance of spectral enhancement?
feature identification
The digital image contains a __ number of rows and columns of pixels:
fixed
Within a single image, the spatial resolution of the image is:
fixed
Spatial resolution of an image is?
fixed once the image is acquired by the satellite
Thermal remote sensing will be most effective for studies pertaining to which of the following ?
forest fires
According to the Stefan-Boltzmann law, the radiative energy emitted by one square meter of an object is equal to a constant multiplied by its temperature raised to the _______ power.
fourth
Multi-sensor image......... is the process of combining relevant information from two or more images into a single image:
fusion
Near Infrared (NIR)
g. Used in monitoring vegetation
While passing through the atmosphere, the solar radiation:
gets absorbed partially
An object with an emissivity less than 1 is called a:
graybody
In sun light, water rich in phytoplankton appears
green
InSar allows to estimate?
ground deformation
Rayleigh's criterion for a rough surface is: (where letters carry their usual meanings).
h > /\/8 cos 0. (wavelength is the weird slashes)
Orbit of a polar satellite is
helical
The albedo of the earth's surface is only about 4%, yet the combined albedo of the earth and the atmosphere is higher. Which set of conditions below best explains why this is so?
high albedo of clouds, low albedo of water
High pass filters highlight:
high intensity components
Spikes in an image can be the resultant of __
higher values of surrounding pixels, and lower values of surrounding pixel
Compressed image can be recovered back by
image decompression
When a light beam emerges from water into air, the average light speed
increases
The refractive index of the ocean water:
increases with salinity
In a standard False Colour Composite (FCC) red color is assigned to:
infrared band
A rainbow nicely illustrates an example of light
internal reflection, refraction
In a curved optical fiber, light
internally reflects in a succession of straight-line paths.
The shortest plane mirror in which you can see your entire image
is half your height.
According to Wein's displacement law, the wavelength at which maximum radiation occurs
is inversely proportional to the temperature
An echo occurs when sound
is reflected from a distant surface.
What does the term "climate noise" refer to?
lack of predictability
Diffuse reflection occurs when the size of surface irregularities is
large compared to the wavelength of the light used.
Generally, which scale maps may not be prepared from satellite data?
large scale
When the reflection of an object is seen in a flat mirror, the distance from the mirror to the image depends on
the distance from the object to the mirror
The value of energy quantum for radiation of any frequency is proportional to:
the frequency
When a virtual image is created in a plane mirror
the image is upright, the image is located behind the mirror, reflected rays diverge
When you look at yourself in a pocket mirror and then hold the mirror farther away, you see
the same amount of yourself.
Different colors of light travel at different speeds in a transparent medium. In a vacuum, different colors of light travel at
the same speed
The reason we can read print from any direction is that
the white part of a page reflects light in all directions.
Which among these remote techniques is most suitable for identifying animal population from dense forest area?
thermal images
What is the importance of fiducial marks in an aerial photograph?
to find the principle point
Scattering of solar radiation by aerosols is the main process limiting visibility in the _______
troposphere
Remote sensing technology provides unbiased recordings.
true
optical images captures at night is an example of passive remote sensing
true
the tentative height of an object can be estimated from an RS imagery
true
__________ has a refractive index of exactly 1.000.
vacuum
Why is infrared radiation used to detect vegetation?
vegetation strongly reflects infrared
Repetitive observations of the same area at equal interval of time, are useful to monitor the dynamic phenomena:
vegetative cover
If a real object is placed in front of a convex mirror (f < 0), then the image is
virtual, erect and reduced in height relative to the object
Which portion of the electromagnetic spectrum is used in a microscope?
visible light
Refraction occurs
when a wave changes speed.
A mirage can occur
when cooler air is above hotter air, when there's a layer of hot air close to the ground, on a hot day
Which of the following is NOT an additive primary color?
yellow
What is OCO-2 data most commonly expressed as?
χCO2, the mole fraction of CO in the air column - while OCO-2 measures reflectance, the data is expressed as a mole fraction
How is LiDAR mechanistically different from RADAR?
LiDAR uses a laser light, not radio waves.
Each colour cycle in a SAR interferogram represents elevation difference of:
𝜆/2
What are wavelength, frequency, amplitude, phase categorized as?
properties of electromagnetic energy
How does the satellite Topex/Poseidon map ocean features?
radar
The energy captured by a remote sensing sensor is
radiance
Remote sensing process involves an interaction between incident ___ and the targets of interest
radiation
A pre-processing method to reconstruct physically calibrated values by correcting the spectral errors and distortions caused by sensors is called:
radiometric correction
Which of the following is a consequence of the refraction of light?
rainbows, mirages, internal reflection
By itself, the term "digital image" usually refers to:
raster image
What color does living vegetation appear as on false-color IR images?
red
With the increase of turbidity, the muddy water appears brown due to the shift of the upward radiance peak towards:
red
Light can be polarized by [___].
reflection, refraction, selective absorption
A person standing waist-deep in a swimming pool appears to have short legs because of light
refraction
Part of a pencil that is placed in a glass of water appears bent in relation to the part of the pencil that extends out of the water. What is this phenomenon called?
refraction
The effect that we call a mirage has most to do with
refraction
A rainbow is formed by [___] within rain droplets.
refraction, dispersion, internal reflection
Remote sensing produces two types of data, observational and inferred. Most of NASA's A train products are inferred. Inferred data is also called
retrievals
The skew distortion error in images is mainly due to __
rotation of the earth
depends on radiation wavelength , size and concentration of atmospheric particles, and depth of atmosphere
scattering
may produce a hazy appearance in the image captured by the sensor
scattering
Which factor interferes the most with passive microwave measurements of SST?
sea surface roughness or cloud cover
If 0 is the angle of scan measured from the nadir, the ground distance swept by the sensor IFOV is proportional to:
sec2θ
If 0 is the angle of scan measured from the nadir, the ground distance swept by the sensor IFOV is proportional to:
sec^20
If 0 is the angle of scan measured from the nadir, the ground distance swept by the sensor IFOV is proportional to
sec^2θ
radiometric error in an image is introduced due to _
sensor properties
Which of the following helps to identify the objects on the earths surface?
signature
Which one of the following helps to identify the objects on the Earth's surface?
signature
visual interpretation is the ___ that an image interpreter apply equally to an image:
skill
When you see a "wet spot" mirage on the road in front of you, you are most likely seeing
sky
Rayleigh scattering occurs when particles are very ___ compared to the wavelength of the radiation
small
A highly polished finish on a new car provides a ____ surface for ____ reflection.
smooth; specular
Blue on a radar precipitation map indicates ____________________.
snow
Where would albedo be greatest?
snow
The arrangement of terrain features which provides attributes: the shape, size and texture of objects, is called
spatial variation
Spectroradiometer can measure
spectral reflectance, spectral transmittance, spectral irradiance, spectral radiance
Pick up the important characteristic of a target which facilitates its identification from the following:
spectral variation, spatial variation, temporal variation, polarisation variation
Which of the following properties characterize an optical sensor?
spectral, radiometric, and geometric performance
Which of the following radiometers measures the intensity of radiation in multiple wavelength bands?
spectroradiometer
For interpolation of satellite data used for monitoring dynamic changes that occur on the earth surface, the most suitable orbit for the satellite is
sun-synchronous orbit
Which of the following materials is the closest to being a true blackbody? a. lampblack b. nanoblack c. super black d. vantablack
super black
In microwave remote sensing __ of an object is measured
surface backscattering
This type of RaDAR stores sequentially received signals in memory over time and adds them:
synthetic aperture
spatial resolution is finest for images obtained through sensors placed at __
terrestrial platforms
It is difficult to see the roadway from a car on a rainy night because the road surface
that is normally a diffuse reflector when dry becomes a mirror surface when wet.
The law of reflection says that
the angle of reflection from a mirror equals the angle of incidence.
What is the electromagnetic spectrum?
the arrangement of electromagnetic radiation
State Wein's Law
the black body radiation curve for different temperatures peaks at a wavelength inversely proportional to the temperature
Assume that LAN is an example of a perfect blackbody radiator. Assume that the wavelength of LAN is 4.0 *10-7m. Determine the temperature at the surface of this star.
Use Wein's Law, which states that: λ = b/T. Since we want to find T, T = b/λ = (2.90*10 )/(4*10 ) = 7250 degrees K.
Short Wave Infrared (SWIR)
Used in determining spectral signatures of objects.
Which of the following would most likely cause nonselective scattering with visible light?
VOCs
'No data' is a:
Value
Repetitive observations of the same area at equal interval of time, are useful to monitor the dynamic phenomena:
Vegetative cover
How is visible light different from all other forms of electromagnetic radiation?
Visible light is the only electromagnetic radiation that is detectable by the human eye.
What range of EM waves do optical sensors detect?
Visible light spectrum, and Infrared
Which two wavelength bands are combined to calculate the Normalized Difference Vegetation Index (NDVI)?
Visible red and near-infrared
The light which our eyes - our "remote sensors" - can detect is part of the:
Visible spectrum
Process of identifying what we see on the images and communicate the information obtained from these images to others for evaluating its significance is known as:
Visual image interpretation
_________ scattering occurs in a medium when electromagnetic radiation transmits from one medium to another medium.
Volume
What do negative values of NDVI (approaching -1) indicate?
Water
The characteristics of electromagnetic radiation are particularly important for understanding remote sensing:
Wavelength and frequency
Which of the following describes the relationship between wavelength and frequency?
Wavelength is inversely proportional to frequency, and frequency decreases as the wavelength goes up.
Which of the following is a true statement?
Web HTML5 APIs provide for interlinkages of geo-locational information from 3D and 2D interactive graphics.
___________ displacement law states that the black body radiation curve for different temperatures peaks at a wavelength _______________ proportional to the temperature
Wein's; inversely
Who was the rocket scientist who led Project Orbit in 1955?
Wernher von Braun
Who coined the term, 'Remote sensing'.
Evelyn L. Pruitt, a geographer
The energy of a light beam is carried by separate photons, yet we do not perceive light as a series of tiny flashes. Why not?
Even a weak light involves many photons per second. Visual responses persist for a short time, so successive photons give the impression of a continuous transfer of energy.
How often does MODIS image the earth?
Every one to two days
Which satellite took the first photograph of earth from space?
Explorer-6
What is the name of the US' first satellite?
Explorer 1
The end lap and side lap of stereo-pairs should be more than 20% and 60% respectively
FALSE
The world map is an example of large scale map FALSE
FALSE
True or False: A maximum likelihood classifier is an example of unsupervised image classification.
False
True or False: Vector is a representation strategy involving sampling attributes at fixed intervals.
False
How does a Landsat satellite differentiate between objects on Earth's surface?
Features on Earth radiate warmth at different frequencies, which show up as different colors on Landsat images
Remote sensing unofficially began when this scientist took aerial photographs from a balloon. Arthur Rudolph Ludwig Roth Konrad Dannenberg Felix Tournachon
Felix Tournachon
RESOURCESAT-1 was launched in 2003 by:
India
Their use is called thermography.
Infrared Imager
The emission of electrons from a metal plate exposed to light depends on the:
Intensity of the light, and frequency of light
The process of using data points with known values to estimate values at unknown points (in same region or nearby region) is called spatial _____.
Interpolation
The coherence length over which there is a strong relationship between amplitudes is;
Inversely proportional to the bandwidth
______________ controls how much light enters the eye by changes the size of the pupil. It is also the color part of your eye.
Iris
A perfectly black body:
Is a diffuse emitter, Absorbs all the radiations of every wave lengths, Emits power of every wave length
An instrument on AURA is the Microwave Limb Sounder. What and how does it function?
It is a passive sensor and takes ozone, water vapor, and greenhouse gas readings at the top of the atmosphere
What is a drawback of passive sensing?
It is dependent on the outside radiation's existence. If there is little or no outside radiation, the satellite cannot function well.
In a photograph, an analyst notices a feature which has straight edges. What can the analyst conclude about the feature?
It is man-made
What orbital path do satellites on the A Train follow?
It is sun synchronous and crosses the equator at 1:30 pm solar time
How is the Boltzmann constant found?
It is the gas constant R divided by the Avogadro constant NA:
An image that shows finer details is said to be of:
Finer resolution
Due to perturbation of the orbit, satellite orbit parameters are frequently updated on measurements carried out by its:
Five ground stations
Spatial resolution of an image is?
Fixed once the image is acquired by the satellite
Remote Sensing unofficially started in ______ when pictures were taken from hot air balloons
France
Which famous French photographer first practiced aerial photography and made photographs of Paris from his balloon in the mid-18th century?
Félix Nadar
Which of these satellites would most likely be in a geostationary orbit?
GOES
__________________ came up with the first idea for a microscope.
Janssen
Joe is working on a project involving extracting details from multiple commercially available databases. Unfortunately, the data all have generic titles. Dean, his boss, recommends that he open a new map session and bring all the data in and then extract that which he needs. Joe feels that, since the databases have extensive metadata, he can simply query that for the specific layers he needs rather than open everything. Who is correct?
Joe is correct
Who first discovered the greenhouse effect?
Joseph Fourier
Juan and Esperanza are working with an image with the data confined between the values 97 and 167. Juan says that he can increase the contrast in the image by applying a linear contrast stretch. Esperanza says that he can increase the contrast in theimage through the histogram equalization method. Who is correct?
Juan and Esperanza are both correct
Landsat-1 was launched on:
July 23, 1972
GIS, Remote Sensing and GPS technologies are:
Generic, digital and spatial
In which orbit the Global Positioning Satellites are?
Geo-synchronous
Often monitoring ice can be difficult due to cloud cover. To correct for the cloud cover which bands of radar are often used (that easily penetrate clouds)?
L Bands
Multi Spectral Scanner (MSS) was on board on which satellite:
Landsat-1
Which of the following satellites are active members of the Morning Constellation (EOS AM)?
Landsat-7 - Terra and Landsats -7 and -8 comprise of the Morning Constellation. EO-1 is no longer active.
Which is the latest Landsat satellite currently in operation:
Landsat-8
For edge detection which spatial filter would be most suitable?
Laplacian
for edge detection which spatial filter would be most suitable?
Laplacian
To achieve the clearest resolution of an image when using a microscope or telescope, which set of conditions would be ideal.
Large aperture; small minimum angle of resolution
Which of the following statements is/are true regarding geospatial databases?
Geospatial databases are typically time stamped in universal coordinated time (UTC)
While passing through the atmosphere, the solar radiation:
Gets absorbed partially
What is the difference between a Global energy balance model and a Zonal, or latitudinal, model? Which is considered to be more accurate and why?
Global models do not account for the discontinuity of energy flow in the system. Zonal models include a part of an equation that accounts for the flow of energy from one latitudinal zone to the next. The Zonal models provide a more clear and accurate picture.
In sun light, water rich in phytoplankton appears:
Green
What is another name for LiDAR?
Laser scanning or 3D scanning.
What is beam attenuation?
Lessening in intensity of beam as it passes through matter
In 1986 NASA defined various data processing levels. What is the difference between level 1 data and level 4 data?
Level 4 data is more processed that Level 1 data. Level 4 data is calculated from Level 1 data, not directly absorbed.
This is a detection system that works on the principle of radar, but uses light from a laser
LiDAR
What are the advantages of LiDAR over RADAR?
LiDAR provide images with less noise
Which of the following types of sensors uses a highly focused beam of light? (a) Sonar (b) Lidar (c) Ground penetrating radar (d) Side-looking radar
Lidar
What are the advantages of lidar over radar?
Lidar provide images with less noise
Lidar uses __, ___ or __ light to image objects.
Lidar uses ultraviolet, visible, or near infrared light to image objects
LiDAR stands for....?
Light Detection and Ranging
What does LIDAR stand for?
Light detection and ranging
What does Lidar stand for and what kind of pulse does it use as a signal?
Light detection and ranging, laser
Why is a beam of white light that passes perpendicularly through a flat pane of glass not dispersed into a spectrum?
Light incident perpendicular to a surface is not deflected, so light of the various frequencies in white light stays together despite the different velocities in the glass.
Why can light waves travel through a vacuum whereas sound waves cannot?
Light waves consist of coupled frequencies in electric and magnetic fields and hence require no material medium for their passage.
Which type of instrument provides the opportunity for each detector to have a longer dwell time, or residence time, over which to measure the energy from each ground resolution cell:
Linear arrays
An image enhancement technique that attempts to improve the contrast in an image by 'stretching' the range of intensity values it contains to span a desired range of values is called?
Linear contrast stretching
An image enhancement technique that attempts to improve the contrast in an image by `stretching' the range of intensity values it contains to span a desired range of values is called?
Linear contrast stretching
As a general rule of thumb, ___________ wavelengths penetrate ___________.
Longer; more - for example, longwave microwave can penetrate tree canopy and the ground
Which type of radiometer can be used by both principles and among multiple wavelengths?
MEMS Radiometer
What do instruments do Terra and Aqua have in common?
MODIS
Which is NOT a commonly used format for images?
MP3
Which of these instruments was introduced in the Landsat Program?
MSS
The most widely used antenna in GPS is
Microstrip antenna
ERS, Envisat, Sentinel and RISAT are example of which type of satellites:
Microwave
The intensity in a synthetic aperture radar image depends on the amount of what backscattered by the target?
Microwave radiation
ERS, Envisat, Sentinel, RISAT and ALOS are:
Microwave satellites
What types of waves are used in modern-day radars?
Microwaves
which type of scattering will be more prominent in polluted environment?
Mie Scattering
What type of scattering is responsible for the white glare around the sun?
Mie scattering
What is a MODIS?
Moderate-resolution Imaging Spectroradiometer
Unhealthy vegetation will reflect __ visible light and ___ NIR?
More, less
A ___ image is one that captures image data at specific frequencies across the Ems, including light from frequencies beyond the visible light range, such as infrared:
Multispectral
How does LiDAR work?
Must mention using a laser to transmit light pulse, and a receiver to measure reflected/backscattered light.
__ is a simple graphical indicator that can be used to analyze remote sensing measurements, and asses whether the target being observed contains live green vegetation or not.
NDVI
Leaves reflect
NIR
In Hyperspectral remote sensing, generally bands are relatively ........ as compared to Multispectral remote sensing:
Narrow
A plant with more chlorophyll will reflect more:
Near-infrared
Vegetation with more chlorophyll will reflect more:
Near-infrared
Allie shines a special flashlight and determines that the light combing out of her flashlight 14 has a frequency of 10 hz. What type of light is Allie's flashlight emitting? Be as specific as possible! If you made a remote sensing image using the type of light coming out of Allie's flashlight, what would the image be most useful at showing?
Near-infrared light (fun fact: this is really good for vegetation) Plants or Vegetation
What is the key difference between active and passive sensors?
Need to say that active sensors emit radiation. Active emit radiation to detect what bounces back, passive sensors just detect what is reflected from the object already.
In N-D visualization, dimension is equal to
No. of bands
Which of the following is used to describe a database that stores and retrieves data in means other than the tabular relations used in relational databases?
NoSQL
Which form of scattering in the atmosphere is NOT dependent on wavelength?
Non-Selective
Which form of scattering in the atmosphere is NOT dependent on wavelength?
Non-selective
An Entity-Relationship (E-R) diagram is an appropriate technique for visualizing the spatial relationships among _______.
Non-structured and structured geospatial data
What is the LandSat 7 band combination (3, 2, 1) typically used for? Traditional false color images Discerning between snow and ice coverage Detecting healthy vegetation Remote sensing urban settings None of the above
None of the above
Which one of the following errors is produced by platform characteristics of the sensor?
None of the above (Missing scan lines, radiometric, skewness)
What is the name of the following equation: NIR - Red / NIR + Red?
Normalized Difference Vegetation Index
The wavelength is the length of:
One wave cycle
MSS, TM and LISS-I sensors are:
Only passive sensors
An object that does not allow any light to pass through is considered to be___________.
Opaque
___________ remote sensing makes use of visible, near infrared and short-wave infrared sensors to form images of the earth's surface by detecting the solar radiation reflected from targets on the ground.
Optical
What detects solar radiation reflected or scattered from the earth, forming images resembling photograpbs taken by a camera high up in space?
Optical Sensors
Which of the following is not a cause of Mie scattering?
Ozone
What is band 8 on the Landsat-8 OLI?
PAN, a panchromatic band measuring across 0.5-0.68 𝜇m
Which A-Train satellite is no longer active?
PARASOL
Which types of images are created when the imaging sensor is sensitive to a wide range of wavelengths of light, typically spanning a large part of the visible part of the spectrum?
Panchromatic
List and define the four types of optical remote sensing systems.
Panchromatic: single channel detector sensitive to radiation in a broad range. Multispectral: multichannel detector with a few spectral bands Superspectral: many spectral bands (>10), narrow ranges in bands Hyperspectral: lots of contiguous spectral bands, >100.
The magnetic field of an electromagnetic waves is:
Parallel to the electric field and to the wave direction
Infrared photography is an example of which of the above two types of Remote Sensing?
Passive
What types of waves are used by active and passive sensors?
Passive seffiors use microwaves Active Sensors use radio waves
What two ways can spectral radiance be measured?
Per unit wavelength, per unit frequency
From which type of aerial photograph can the height of a feature be best determined?
Photograph acquired at low oblique
When electrons return to their ground state, the electrons emit____________________.
Photons
A and B are two towers of equal height diametrically opposite on either side of the nadir point, at 3 km and 5 km distances. Which one of the following statements is correct?
Height displacement of A will be less than that of B
A and B are two towers of equal height diametrically opposite on either side of the nadir point, at 3 km and 5 km distances. Which one of the following statements is correct? A.Height displacement of A will be less than that of B B.Height displacement of B will be less than that of A C.Height displacement of A and B is equal D.Height displacement of A and B will be towards each other
Height displacement of A will be less than that of B
the image of an urban area has __ spatial frequency
High
High pass filters highlight:
High intensity components
Base of image pyramid contains:
High resolution
Choose from below an advantage and disadvantage of aerial images over satellite images respectively
High resolution and low contrast
Vegetation has a remarkably ...... reflection in the near infrared channel and a ...... reflection in the visible red channel:
High, low
An object with a ___, and a larger _____ facing perpendicular to the radar's energy and composition of a more ___ material will send relatively more backscattered energy to the radar set.
Higher Density, Surface Area, and Reflective
In which technique, histogram of the original image is redistributed to produce a uniform population density:
Histogram equalization
What is meant by Earth's "Radiation Budget"?
How much energy the Earth gets from the Sun and how much energy the Earth-System radiates back to outer space.
What is the purpose of a low earth orbit?
Human Spaceflight
"All bodies at temperatures above absolute zero degree emit electromagnetic radiation at different wave length", is known as:
Plank's law
Nadir
Point on Earth's surface in line with the RS system and the center of the Earth
What is Raman scattering most dependent on?
Polarizability of the molecules
Once data is collected, images MAY need to be corrected. They are typically corrected through two methods. (A) Which method gives a scale to the pixel values? (B) Which method rescales each frequency band to its minimum value?
(A) Radiometric correction (B)Atmospheric correction
Consider the following statements regarding the satellite imaging: 1. The satellite orbit is fixed in the inertial space 2. During successive across-track imaging, the earth rotates beneath the sensor 3. The satellite images a skewed area Which one of the following is correct regarding the above statements?
(a) 1, 2, 3
The emission of electrons from a metal plate exposed to light depends on the:
(a) Intensity of the light, and (b) Frequency of light
Which of the following is not a type of image resolution? (a) Special (b) Spatial (c) T emporal (d) Spectral
(a) Special
Which of the following is not a type of radiometric correction used in image processing when there is interference with the radiance measured by an instrument? (a) Noise removal (b) Ozone depletion correction (c) Haze correction (d) Sun angle correction
(b) Ozone depletion correction
Due to scan geometry of a satellite sensor: (a) The off-nadir resolution is degraded (b) The ground distance swept by the senor, IFOV is proportional to sec2θ, where θ is the angle of scan measured from the nadir (c) The details towards the edge of the scan get compressed (d) All of these
(d) All of these
Earth observations from a satellite platform provides: (a) Synoptic view of a large area (b) Constant solar zenith angles and similar illumination conditions (c) Repetitive observations of the same area with intervals of a few minutes to a few weeks (d) All of these
(d) All of these
Leaf reflectance depends primarily on: (a) The pigments (b) Internal cell structure (c) Equivalent water content (d) All of these
(d) All of these
The optical property of a water body depends on: (a) Absorption by the dissolved material (b) Absorption by the suspended particulate matter (c) Scattering by the suspended particulate matter (d) All of these
(d) All of these
Which of the following is not a reason why remote sensing is ideal for use in Natural Sciences? (a) It can be applied at any scale (b) It can monitor change over time (c) It minimizes the need for fieldwork in dangerous, isolated and sensitive areas (d) It will always be more reliable than fieldwork studies
(d) It will always be more reliable than fieldwork studies
Pick up the correct statement from the following:(a) In remote sensing technique, the observation place, is called a platform (b) Platforms may be either stationary or mobile (c) Spatial resolution of the imaging system becomes poorer with increase of platform height. (d) Area coverage of the imaging system increases with the increase of the platform altitude. (e) All of these
(e) All of these
In ___ imaging, like other spectral imaging, collects and processes information from across the Ems. The goal of hyperspectral imaging is to obtain the spectrum for each pixel in the image of a scene, with the purpose of finding objects, identifying materials, or detecting processes:
Hyperspectral
Pick up the correct statement from the following:(a) The first man-made satellite, Sputnik was launched on 4th October, 1957 (b) The US's Explorer 6 transmitted the first picture of the earth in August 1959 (c) Television Infrared Observation Satellite (TIROS) designed for meteorological observations, started systematic earth observations from space from 1, April, 1960 (d) U.S.A.'s highly secret mission CORONA started the collection of intelligence photography in 1960 (e) All of these.
(e) All of these.
An object that is 18 cm from a converging lens forms a real image 22.5 cm from the lens. What is the magnification of the image?
-1.25
Rank these materials from smallest to highest albedo. I. Snow II. Asphalt III. Bare Soil IV. Green Grass
II. III. IV. I.
Satellite sensors LISS-I, LISS-II, LISS-III and LISS-IV were on-board:
IRS series of satellites
Is the scattering elastic or inelastic? Brilloiun Debye Raman Thompson Compton Rayleigh
I___Brilloiun E___Debye I___Raman E___Thompson I___Compton E___Rayleigh
Microwave or Radar
.1 to 100 cm -Partially available for remote sensing as the longer wavelengths in the Region pass through clouds, fog, and rain -Used in radar.
Photographic Ultraviolet
.3 to .4 um Available for remote sensing the Earth & can be imaged with photographic film
Visible
.4 to .7 um -Available for remote sensing the Earth & can be imaged with photographic film -Helps satellites detect colors that the human eye can see.
Infrared
.7 to 100 um Available for remote sensing the Earth & can be imaged with photographic film
Reflected Infrared
.7 to 3 um Partially available for remote sensing as shorter wavelengths in the Region can be imaged with photographic film
The objective of image interpretation is:
Identification and recognition of objects
Modification of an image to alter its impact on viewer / interpreter is?
Image Enhancement
Which is first step in digital image processing:
Image acquisition
Compressed image can be recovered back by
Image decompression
In which process of remote sensing these fundamental parameters(size, shape, tone, texture, site, association, shadow, and pattern) are used:
Image interpretation
The pulse length of a SLAR system having range resolution 30m and look angle 65 is _
0.18 usec
What is the most common wavelength band which electro-optical scanners work within?
0.3 and 14μm
The visible wavelengths cover a range from approximately:
0.4 to 0.7 μm
If temperature is 200 K and wavelength is 30 um, what is the spectral radiance?
0.5 W/m2
The maximum sun's radiation occurs around:
0.55 μm wave length
The infrared portion of EMR lies between
0.7 to 14 um
Ultraviolet
03 to .4 um -Partially available for remote sensing as shorter wavelengths in the Region are absorbed by ozone in the Earth's atmosphere -Not suitable for remote sensing because it is blocked by the ozone layer.
X-ray
03 to 30 nm Not available for remote sensing as the Region is entirely absorbed by the Earth's atmosphere
The reflectivity of a surface ranges between zero and _____.
1
Consider the following statements regarding the satellite imaging: 1. The satellite orbit is fixed in the inertial space 2. During successive across-track imaging, the earth rotates beneath the sensor 3. The satellite images a skewed area Which one of the following statements is/are correct?
1,2,3
Consider the following statements regarding the satellite imaging: 1. The satellite orbit is fixed in the inertial space 2. During successive across-track imaging, the earth rotates beneath the sensor 3. The satellite images a skewed area Which is true ?
1,2,3
Consider the following statements regarding the satellite imaging:1. The satellite orbit is fixed in the inertial space 2. During successive across-track imaging, the earth rotates beneath the sensor 3. The satellite images a skewed areaWhich one of the following is correct regarding the above statements?
1,2,3
The process of examining a remote sensing image and manually identifying the features in that image is called:
Image interpretation
If the velocity of light through as unknown liquid is measured at 2.4 x 108 m/s, what is the index of refraction of this liquid?
1.25
The refractive index of water is_____________.
1.333
What is the CERCES resolution at nadir view on TRMM?
10 km
A cell with 1m spatial resolution covers an area of 1m , whereas a pixel with 0.1m spatial resolution covers an area of:
100cm^2
Normally, the distance of remote sensing satellites from the Earth is about:
1050 km
In the year 1986 - SPOT French Earth Observation Satellite provided first time spatial resolution at:
10m PAN and 20 m multispectral
If temperature is 350 K and wavelength is 15 um, what is the spectral radiance?
11 W/m2
A multispectral scanner is mounted aboard an airplane which is at an altitude of 15,000 metersabove the ocean. If the IFOV of this system is 0.25 radians, what is the ground area viewed bythis sensor? (Hint: D = H'β)
11 km2
In geographic coordinate system 1° at equator is equivalent to:
111.32km
In a topographic map of 1:50,000 scale, what is the actual distance between two points A and B which lies 25 cm apart?
12.5 Km
If a satellite-based pushbroom sensor has a row of 5,000 CCD cells aligned perpendicular to the satellite's motion, and the swath width is 600 kilometers, what is the ground sampling distance (spatial resolution)?
120 meters
Light enters a glass plate at an angle of incidence of 25°. If the index of refraction of a glass is 1.6, the angle of refraction is
15 degrees
What is the wavelength range for far-infrared?
15-1000 μm
First aerial photograph was taken from a hot air balloon in the year:
1858
What will be the ground range distance calculated for a flat terrain with a given flying height of 20km and slant range 5km?
19.4 km
The first space-based photograph by Viking Sounding Rocket was taken on:
1947
In which year was MODIS first launched into orbit?
1999
he various stages occuring in GPS system are described below: 1. Generation of an output to the user 2. Detection of the GPS signals 3. Processing the data in the built-in-computer 4. Decoding the GPS signal. The correct sequence of the stages is:
2,4,3,1
A 512 x 512 image of 8 bits would require computer memory to store:
2.1 MB
A 512 x 512 image of 8 bits would require computer memory to store:
2.1 mb
Although carbon dioxide is the most important greenhouse gas, methane molecules trap heat with an efficiency that is _____ times larger than that of a molecule of carbon dioxide
20
If a 15 inch cylinder is 60 in. away from a convex lens, what would the cylinder's image distance be?
20 in
Medium Earth orbits are generally at what altitude range?
2000-36000 km
For C band Synthetic Aperture Radar (SAR) with Doppler band width of 1300 Hz, the coherence length loch is:
230 km
How many satellites are in the GPS system?
24
Weather satellites orbit the Earth in around
24 hours
If three 8-bits bands are used to create a FCC then what would be pixel color depth:
24-bits
GPS measurement is accurate to within 25 meters (95% confidence). This means that you can be 95% sure that your measurement is somewhere within a ... meter error circle and there is a 5% chance that the error is LARGER than ... meters.
25
An 8-bits image can have ...... total number of pixel values:
256
How many total shades of grey or colors an 8-bits image will have:
256
A concave mirror forms a real image at 42 cm from the mirror surface along the principal axis. If the corresponding object is at a 88 cm distance, what is the mirror's focal length?
28 cm
Thermal Infrared
3 to 14 um -Available for remote sensing the Earth BUT CANNNOT be imaged with photographic film -Used in determining the temperature of an object.
In electromagnetic radiation, electrical and magnetic fields travel at?
3.00×10^8 m/s
The combined albedo of the earth and the atmosphere is approximately
30%
In the absence of aerosols our visual range would be approximately ________ km, limited by scattering by air molecules.
300
calculate the temperature of an object with a peak emittance wavelength of 9.5 um?
32 degrees C
What is the currently accepted value of dT?
33 degrees Kelvin, and is a function of the efficiency of the infrared absorption
The altitudinal distance of a geostationary satellite from the earth is about:
36, 000 km
The altitudinal distance of a geostationary satellite from the earth his about:
36,000 km
How many A-Train satellites are currently active?
4 satellites
Energy of an EMR of wavelength 450nm is_
4.4195 x 10^-29 joules
The human eye, as a remote sensor, responds to what spectral range?
400 - 700 nm
the average radiant exitance from a clear water body at 300 k is _?
452 W/m^2
If a star's surface temperature is 30,000 k, how much power does a square meter of its surface radiate?
46 billion watts per square meter
How many Navstar satellites are theoretically necessary to locate and track a GPS receiver?
4 - Navstar relies on a three-dimensional triangulation method, requiring four satellites
A pulse of light is sent down from a sensor (using lidar) toward Earth. The sensor is orbiting the earth from a distance of approximately 80 km. The pulse is intended to measure the height of a mountain. If the pulse takes .0005 seconds to reach the mountain and get back (to the sensor), how high is the mountain (take the speed of light to be 3 x 105 km/s)?
5.0 km
A pulse of light is sent down from a sensor (using lidar) toward Earth. The sensor is orbiting theearth from a distance of approximately 80 km. The pulse is intended to measure the height of amountain. If the pulse takes .0005 seconds to reach the mountain and get back (to the sensor),how high is the mountain (take the speed of light to be 3 x 105 km/s)?
5.0 km
What does 1mm on a map drawn at a scale of 1:50,000 represent on the ground?
50 metres
Because of the loss of color accuracy, modern 3D glasses use polarizing filters instead of color filters to achieve the 3D effect (this is called stereoscopy). Stereoscopy works because the filters cause each eye to view a different image. When the brain reassembles the two images into one, it perceives depth. What is the intensity of the unpolarized light after passing through one of these filters (note: assume perfect polarizing efficiency)?
50%
What is the flying height, when the differential parallax is given as 0.5 inches for an object of 100 feet height and photo base length 2 inches?
500 ft
Global Positioning Service (GPS) uses 24 satellites in:
6 Orbits
GPS uses 24 satellites in:
6 orbits
If a virtual image is formed 10.0 cm along the principal axis from a convex mirror with a focal length of 15.0 cm, what is the object's distance from the mirror?
6.0 cm
If you stand 3.0 m in front of a flat mirror, how far away from you would your image be in the mirror?
6.0 m
If a laser beam is reflected off a mirror lying on a table and bounces off a nearby wall at a 30 degree angle, what was the angle of incidence of the beam on the mirror?
60 degrees
calculate the flying height above mean sea level, if the equivalence value is 1 inch = 1km, focal length 5 inches and ground elevation is 1000m
6000,
the spectral range of NIR region in the EMS is __
700- 1500 nm
Calculate the synthetic aperture length of a SAR system having antenna length of 8m and wavelength of 7.5 cm flying at an altitude of 600km and a depression angle of 50 degrees.
7342.9 m
As of 2017, how many Landsat missions have taken place?
8
Calculate the energy of a photon having a wavelength of 230 nanometers.
8.65 x 10^-19 J or 5.4eV
The normal altitude of near orbiting remote sensing satellite is about:
850 km
The normal altitude of near polar orbiting remote sensing satellite is about:
850 km
If a pixel of an image is having 30m resolution, how much ground area it would represents:
900 m2
If a pixel of an image is having 30m resolution, how much ground area it would represents:
900 m^2
Gamma Ray
< .03 nm Not available for remote sensing as the Region is entirely absorbed by the Earth's atmosphere
Radio
> 100 cm Not normally used for Remote Sensing the Earth
"An Electromagnetic wave falls on to a boundary between two losses less homogeneous media with different refractive indices, a part of the wave is reflected back to the incident medium and the rest is transmitted on to the second media". This phenomenon is known as: (A) Fresnel reflection (B) Fresnel refraction (C) Snell's law (D) None of these
A
A and B are two towers of equal height diametrically opposite on either side of the nadir point, at 3 km and 5 km distances. Which one of the following statements is correct? (A) Height displacement of A will be less than that of B (B) Height displacement of B will be less than that of A (C) Height displacement of A and B is equal (D) Height displacement of A and B will be towards each other
A
A passive sensor uses: (A) Sun as the source of energy (B) Flash light as a source of energy (C) Its own source of energy (D) None of these
A
Geodimeter is based on: (A) Propagation of modulated light waves (B) Propagation of infrared radiation (C) The visible light as carrier with frequency of the order of 5 × 1014 Hz (D) High frequency radio waves
A
If flying height of a spacecraft is H, the length of air base is B and the parallax difference between two points is dp, then the difference in height (A) h = dp/(B/H) (B) h=(B/H)dp (C) h = dp/(H/B) (D) h = (H/B) dp
A
The entire range of the electromagnetic spectrum spans a large spectrum of wave lengths varying from: (A) 10-10 to 106 m (B) 10-8 to 106 m (C) 10-10 to 1010 m (D) 10-8 to 108 m
A
The part radiation due to scattered/diffused radiation entering the field of view of a remote sensor other than that from the required target, (A) Reduces the contrast of the image and also its sharpness (B) Increases the contrast of the image but reduces the sharpness (C) Increases both the contrast and sharpness (D) Reduces the contrast but increases the sharpness
A
The reflectance from a surface is called specular reflection if it follows: (A) Snell's law (B) Lambert's cosine law (C) Planktan's law(D) All of these
A
The refractive index of the ocean water: (A) Increases with salinity (B) Increases with temperature (C) Decreaseswithsalinity (D) Decreases with temperature
A
The value of energy quantum for radiation of any frequency is proportional to: (A) The frequency (B) The reciprocal of the energy (C) The square of the frequency (D) The square root of the frequency
A
Which one of the following parameters is accurate for DGPS? (A) Positional accuracies ~ 1 - 2 m if rover is less than 1-2 km from the reference station (B) Positional accuracies ~ 2 - 5m if rover is less than 2-5 fm from the reference station (C) Positional accuracies ~ 5 - 10 m if rover is less than 5-10 km from reference station (D) Positional accuracies ~ 5 - 10 m if rover is less than 25 km
A
Which of the following statements is true regarding geospatial data precision?
A GIS dataset built to map "small scale phenomena" may be inappropriate to use in "large scale" analysis
Which of the following is produced by atmospheric scattering?
A hazy appearance in the blue end (400-500 nm) of the visible spectrum
Which of the following is an accurate statement about a hillshade?
A hillshade is a process that creates a shaded relief from a surface raster by considering the illumination source angle and shadows
SAR Interferometry technique requires:
A pair of images
Remote sensing image is:
A raster of regularly spaced sample points
If the light from the sun is passed through a prism or a diffraction grating, the resulting spectrum contains a rainbow of color with many very narrow dark bands. This spectrum is called a(n)
A. Absorption spectrum
Lambertian reflectance is a property that defines the ideal surface for what type of reflection?
A. Diffuse
1. Refraction is the bending of light as it passes at an angle from one medium (e.g., air) into another because [___].
A. both the speed and the wavelength changes.
Considering the picture at this station, label the components of earth's radiation identified in the picture. Be sure to indicate in your answer the role each of these components play in Earth's Energy Budget
A: Solar Incident Energy..............Absorbed Solar Incident Energy raises the Earth's temperature B: Earth's Emitted Energy.......Heat energy leaves the Earth's system and lowers the temperature. C: Solar Reflected Energy........Surface Albedo lowers percentage of Solar incident energy that reaches the surface lowering the Earth's temperature
Label each type of sensing with active (A) or passive (P)
A___Radar altimetry A___LiDAR A___Precipitation radar P___Radiometer
Radiometric Resolution
Ability to discriminate small differences in energy
The spatial resolution of most of the bands of the Landsat Enhanced Thematic Mapper Plus sensor is ________________ not including the panchromatic and thermal infrared bands.
About 30 meters
What is achromatic vision
Achromatic vision- The perceptionby the human eye of changes in brighmess, often used to describe the perception of monochrome or black and white scenes.
There are two main modes of scanning to acquire multispectral image data:
Across-track and along-track scanning
RADAR is an example of which of the above two types of Remote Sensing?
Active
Receives signals reflected, refracted, or scattered by Earth's surface and atmosphere.
Active
The instruments which provide electromagnetic radiation of specified wave length or a band of wave lengths to illuminate the earth surface, are called:
Active sensors
What is an ALI?
Advanced Land Imager
What is an ASTER?
Advanced Spaceborne Thermal Emission and Reflection Radiometer
What is an AVHRR?
Advanced Very High Resolution Radiometer
The "A" in A-Train satellites stands for:
Afternoon
Unsupervised image classification technique?
Aggregates pixels into natural spectral groupings/clusters
What is georeferencing?
Aligning images with ground control points on the Earth's surface
What is the purpose of image classification? Landuse and landcover mapping, Lithological mapping, Alteration mapping, All of the above
All of the above
Which of the following are variants of false color? Pseudocolor Density slicing Choropleth Two of the above All of the above
All of the above
Pick up the correct statement from the following: (a) Phase of a wave is expressed as a fraction of a period with respect to a reference (b) Phase is usually specified by angular measure with one period being 360° (c) The reference for finding the phase of a wave is taken from the previous passage through zero from the negative to the positive direction.
All of these
Pick up the correct statement from the following: (a) When the electric field oscillates in the direction of the electric vector, a plane polarised wave is formed. (b) When the electric vector is in the plane of incidence, vertical polarisation is formed. (c) When the electric vector is at right angles to the plane of incidence, horizontal polarization wave is formed. (d) The plane containing the incident ray and normal to the reflecting surface at the point of incidence is called the plane of incidence.
All of these
Which one of the following statements is correct?
All of these (During the day, earth reflects solar radiation. During the day earth reflects both solar radiation the emission from its surface. During the night, earth emits radiation from its surface.)
The basic requirement of any sensor system, is:
All of these (Radiometric resolution, Spatial resolution, Spectral resolution, Temporal resolution)
Pick up the correct statement from the following:
All of these (The distance between two successive crests or troughs of a wave, is called, the wave length. The wave length is measured in metres and a fraction of a metre. The wave length is generally denoted by λ. The length of the crest from the midpoint, is called amplitude.)
What is the relationship between along track and across track scanners?
Along track has less moving parts and is less expensive than across track
Which type of satellite systems are linear arrays used on?
Along-track scanners and Whiskbroom scanners
Which one of the following geometric errors of satellite sensors is random?
Altitude variation
'A time varying electric field produces a magnetic field.' This phenomenon is called:
Ampere Maxwell's law
The first requirement for remote sensing is to have:
An energy source
A positive magnification signifies __________________; A magnification that is less than 1 signifies __________________________
An erect image: An image smaller than the object
What is a composite, in the context of remote sensing?
An image where multiple satellite images have been combined to produce a new, often more detailed, image.
Choose the option below which does not occur when light passes from a medium with a higher refractive index to that of a lower refractive index. An increase in frequency An increase in velocity An increase in wavelength A bend away from the normal line
An increase in frequency
A radiometer is....
An instrument which measures EM intensity in a band of wavelengths
What is Blackbody Radiation?
An object or system which absorbs all radiation that hits it and then re-radiates the energy which is characteristic of this radiating system only NOT on the type of radiation which is radiant upon it.
Which form of representation does an image print use?
Analog
which atmospheric correction method is most useful for easy detection of haze from the images and why?
Angular information based correction; multiple angles of observation
Which of the following is a key strength of principal components analysis (PCA)?
Anomaly detection
What is beam attenuation and how does it occur?
Answer: Attenuation is the reduction of the intensity of an x-ray beam as it traverses matter. The reduction may be caused by absorption or by deflection (scatter) ofphotons from the beam and can be affected by different factors such as beam energy and atomic number of the absorber.
Programs that have been developed to provide a more stream-lined interface with a particular data format or schema are termed __________.
Application Program Interfaces (API)
The purpose of georeferencing is to:
Assigning geographic location information
The spectral region of the electromagnetic radiation which passes through the atmosphere without much attenuation is known as:
Atmospheric window
Parts of the spectrum which are not severely influenced by atmospheric absorption are useful to remote sensors, are called:
Atmospheric windows
What is another name for the weakening of lightbeams by scattering or absorption?
Attenuation
_________________ is the reduction of the intensity of an x-ray beam as it traverses matter
Attenuation
On a cross-track scanner, objects seemingly fall __________ the ___________.
Away from; nadir line
Different rows of a RADAR image are associated with different:
Azimuth location
What is the best definition for blackbody.
A hypothetical ideal radiator that absorbs and re-emits all incident energy.
'A time varying electric field produces a magnetic field.' This phenomenon is called: (A) Hertz's law (B) Ampere Maxwell's law (C) Faraday's law (D) Kirchoff's law
B
Due to perturbation of the orbit, satellite orbit parameters are frequently updated on measurements carried out by its (A) Six ground stations (B) Five ground stations (C) Four ground stations (D) Three ground stations
B
For interpolation of satellite data used for monitoring dynamic changes that occurs on the earth surface, the most suitable orbit for the satellite is: (A) Circular orbit (B) Sun-synchronousorbit (C) Near polar orbit (D) None of these
B
In case of reflection and refraction of electromagnetic radiation, (A) Angle of incidence = angle of refraction (B) Angle of incidence = angle of reflection (C) Angle of refraction =sum of the angles of incidence and refraction (D) All the above
B
Orbital radius of GPS satellites is approximately: (A) 15,200 km (B) 26,600 km (C) 18,400 km (D) 36,000 km
B
The arrangement of terrain features which provides attributes: the shape, size and texture of objects, is called: (A) Spectral variation (B) Spatial variation (C) Temporalvariation (D) None of these
B
The interaction of the electromagnetic radiation produced with a specific wave length to illuminate a target on the terrain for studying its scattered radiance, is called: (A) Passive remote sensing (B) Active remote sensing (C) Neutral remote sensing (D) None of these
B
The maximum sun's radiation occurs around: (A) 0.4 um wave length (B) 0.55 u wave length (C)0.7 u wave length (D) None of these
B
The most widely used antenna in GPS is (A) Parabolic antenna (B) Microstrip antenna (C) Horn antenna (D) Slotted antenna
B
The normal altitude of GPS satellite is about (A) 16,200 km (B) 20,200 km (C) 24,400 km (D) 36,100 km
B
The spectral region of the electromagnetic radiation which passes through the atmosphere without much attenuation is known as: (A) Ozone hole (B) Atmospheric window (C) Ozone window (D) Black hole
B
Which of the following is NOT an advantage to LiDAR over RADAR? A. Higher spatial resolution B. Can operate in the presence of cloud cover C. Less beam divergence D. Can detect smaller objects
B
Which one of the following helps to identify the objects on the earth surface? (A) Atmospheric window (B) Signature (C) Radiometricerror (D) None of these
B
ndex n1) on another medium (refractive index m2); (A) The angle of incidence is equal to the angle of refraction (B) The angle of refraction r) is given by sin (C) Both (a) and (b) (D) Neither (a) nor (b)
B
In which image file format the first line of the first band followed by the first line of the second band, followed by the first line of the third band, interleaved up to the number of bands:
BIL
The first pixel for all bands in sequential order, followed by the second pixel for all bands, followed by the third pixel for all bands, etc., interleaved up to the number of pixels is called:
BIP
In which image file format each line of the data followed immediately by the next line in the same spectral band?
BSQ
The amount of absorption of a material is directly proportional to its concentration. Which among thee following satisfies this condition?
Beer Lambert's Law
Refraction
Bending of radiation through a medium
Diffraction
Bending radiation around a corner/boundary
What does a CERES measure?
Broadband radiative energy flux
Coherence of two electromagnetic waves takes place if their phase difference is: (A) Constant in time (B) Constant in space (C) Constantintimeandspace (D) None of these
C
Formation of snow occurs if the cloud temperature is (A) Just above the freezing point (B) At the freezing point(C) Below the freezing point(D) None of these
C
In GPS, receivers used are; (A) Electronic clocks (B) Atomic clocks (C) Quartz clocks (D) Mechanical clocks
C
Remote sensing techniques make use of the properties of ___________ emitted, reflected or diffracted by the sensed objects: (A) Electric waves (B) Sound waves (C) Electromagnetic waves (D) Wind waves
C
The altitudinal distance of a geostationary satellite from the earth is about: (A) 26,000 km (B) 30,000 km (C) 36,000 km (D) 44,000 km
C
The changes in the reflectivity/emissivity with time, is called: (A) Spectral variation (B) Spatial variation (C) Temporalvariation (D) None of these
C
The instruments which provide electromagnetic radiation of specified wave length or a band of wave lengths to illuminate the earth surface are called: (A) Sensors (B) Passive sensors (C) Active sensors (D) None of these
C
The ratio of the total solar radiant energy returned by a planetary body to the total radiant energy incident on the body, the called: (A) Reflectance (B) Reflectance factor (C) Albedo (D) None of these
C
The reflection of solar energy is characterised by the water content in the leaf, in the reflective optical infrared: (A) Visible (0.4 - 0.7 um) region (B) Near-IR (0.7 - 1.3 um) region (C) Short wave-IR (1.3 - 2.7 um) region (D) None of these
C
Which one of the following statements regarding remote sensing is correct? (A) The interaction of the electromagnetic radiation with the target (B) The emission of electromagnetic radiation from the target (C) Both (a) and (b) (D) Neither (a) nor (b)
C
While propagating through homogeneous, isotropic media, (A) Directions of both the fields are orthogonal (B) Both the fields are at right angles to the direction of propagation (C) Both (a) and (b) (D) Neither (a) nor (b)
C
Which of the following relationship between the wavelength, and frequency and th speed (C) of the electromagnetic wave is correct?
C = v/\ (wavelength symbol)
Which one of the following relationship between the wave length (λ), and frequency and the speed (C) of the electromagnetic wave is correct ?
C = vλ
Which one of the following relationship between the wave length (λ), and frequency and the speed (C) of the electromagnetic wave is correct?
C = vλ
Which one of the following statements regarding remote sensing is correct? A. The interaction of the electromagnetic radiation with the target B. The emission of electromagnetic radiation from the target C. Both A. and B. D. Neither A. nor B.
C. Both A. and B.
Which is not an inskument used in remote sensing? A. TM B. ETM+ C. HM D. MSS E. RAR
C. HM
The changes in the reflectivity/emissivity with time, is called: A. Spectral variation B. Spatial variation C. Temporal variation D. None of these
C. Temporal variation
Which one of the following statements regarding remote sensing is correct. A.The interaction of the electromagnetic radiation with the target B.The emission of electromagnetic radiation from the target C.both (a) and (b) D.Neither (a) nor (b)
C.both (a) and (b)
Remote sensing techniques makes use of the properties of-----emitted, reflected or diffracted by the sensed objects: A.electric waves B.soundwaves C.electromagnetic waves D.wind waves
C.electromagnetic waves
In which colour combination, subtractive colour scheme is used?
CMYK
Cities often turn up very bright in radar images due to the ______________________.
Cardinal effect - so named for the cardinal directions, since cities are usually oriented in those directions
Why does the same object have multiple spectral signatures?
Change in composition
What are these linear arrays (referenced in #15) principally made up of?
Charge-coupled devices
____________ clouds would best reflect out-going __________________ radiation back toward the earth to warm the surface.
Cirrus; infrared
The process of turning remote sensing image into meaningful categories representing surface conditions or classes is called?
Classification
Generally, satellite images of Moon's surface are:
Cloud free
Which two satellites were launched in the same payload?
CloudSat and CALIPSO - both satellites were launched from Vandenberg AFB in April 2006 in a Delta-II rocket
Cloud formation frequency is most strongly dependent upon:
Cloud condensation nuclei
If electric permittivity and magnetic permeability of the medium are respectively 'E' and 'u', then the velocity (Cm) of the electromagnetic wave in the medium is given by:
Cm = 1/v8 u
What is a false color image also known as?
Color-infrared
Characteristic absorption features in the spectra is produced by _
Composition of the target
A person who has myopia suffers from a lens without adequate local length. A _____________ Lens can correct the image.
Concave
Coherence of two electromagnetic waves takes place if their phase difference is:
Constant in time and space
In Hyperspectral remote sensing the EM Spectrum is:
Continuous
In hyperspectral remote sensing the EM Spectrum is:
Continuous
Expands the original input values to make use of the total range of the sensitivity of the display device is called:
Contrast enhancement
A camera uses a _________ to form a _________ image.
Converging lens, real image
When an angle of refraction reaches 90 degrees, it is called the __________________ angle.
Critical
A perfectly black body: (A) Is a diffuse emitter(B) Absorbs all the radiations of every wave lengths (C) Emits power of every wavelength (D) All the above
D
A reduction of nitrogen nutrient in plants: (A) Affects leaf colour(B) Reduces pigment concentration (C) Increase the visible reflectivity (D) All of these
D
Critical angle of electromagnetic radiation takes place if (A) Angle of incidence is equal to angle of refraction (B) Angle of incidence is greater than the angle of refraction (C) Angle of incidence is equal to 90° (D) Angle of refraction is equal to 90°
D
Crop Acreage and Production Estimation (CAPE) was funded and taken up in 1983 by: (A) USA (B) European Union (C) Russia (D) India
D
DGPS is based on the concept that bias errors in the position of locations in a given local area, are same if their distances are within (A) 25 km (B) 50 km (C) 75 km (D) 100 km
D
Due to scan geometry of a satellite sensor: (A) The off-nadir resolution is degraded (B) The ground distance swept by the senor, IFOV is proportional to sec2 of scan measured from the nadir (C) The details towards the edge of the scan get compressed (D) All of these
D
Earth observations from a satellite platform provide: (A) Synoptic view of a large area (B) Constant solar zenith angles and similar illumination conditions (C) Repetitive observations of the same area with intervals of a few minutes to a few weeks (D) All of these
D
Electromagnetic radiation: (A) Produces a time varying magnetic field and vice versa (B) Once generated, remains self-propagating (C) Is capable to travel across space (D) All of these
D
Electromagnetic spectrum contains: (A) Gamma rays (wave length < 10-10 m) (B) Ultraviolet rays (wave length < 10-6 m) (C) Infrared rays (wave length < 10-4 m) (D) All of these
D
Leaf reflectance depends primarily on: (A) The pigments (B) Internalcellstructure (C) Equivalent water content (D) All of these
D
Pick up the correct definition from the following with response to GIS. (A) Common boundary between two areas of a locality is known as adjacency (B) The area features which are wholly contained within another area feature, is known so containment (C) The geometric property which describes the linkage between line features is defined as connectivity (D) All of these
D
Pick up the correct statement from the following (A) The ratio of the up flux and down flux just above the snow surface, is called albedo (B) Spectral albedo of snow is calculated for the semi-infinite snow thickness (C) Water equivalent height of snow is the height of water column obtained by melting snow (D) All of these
D
Pick up the correct statement from the following: (A) A graphical representation of spectral reflectance verses the various growth stages of a crop, depicts a phonologic pattern (B) The changes in the polarisation of the radiation reflected or emitted by an object, is known as polarisation variation (C) Thedegreeofpolarisationisacharacteristicoftheobjectwhichhelpsintheidentificationof the object (D) All of these
D
Pick up the correct statement from the following: (A) For the same feature, the photograph taken from the satellite vertically above the aircraft, the height displacement is lesser than the aerial photograph (B) The scale of the aerial photograph depends upon the scale of the topography (C) The feature at the principal point has no height displacement (D) All of the above
D
Pick up the correct statement from the following: (A) In remote sensing technique, the observation place, is called a platform (B) Platforms may be either stationary or mobile (C)Spatial resolution of the imaging system becomes poorer with increase of platform height (D) All of these
D
Pick up the correct statement from the following: (A) Permeability is a measure of conducting the magnetic lines of force in the material (B) Permeability is a measure of the extent to which magnetic lines of force can penetrate a medium (C) Permeability is expressed as the ratio of the magnetic flux density (B) to the field strength of the magnetizing field (D) All of these
D
Pick up the correct statement from the following: (A) Phase of a wave is expressed as a fraction of a period with respect to a reference (B) Phase is usually specified by angular measure with one period being 360° (C) The reference for finding the phase of a wave is taken from the previous passage through zero from the negative to the positive direction (D) All of these
D
Pick up the correct statement from the following: (A) Phytoplankton contains photosynthetically active pigment (B) An increase of phytoplankton increases the back scattering in the green region (C) An increase of phytoplankton absorbs the bule region rapidly (D) An increase of phytoplankton decreases the back scattering in the green region
D
Pick up the correct statement from the following: (A) The first man-made satellite, Sputnik-l' was launched on 4th October, 1957 (B) The United State's Explorer 6 transmitted the first picture of the earth in August 1959 (C) Television Infrared Observation Satellite (TIROS) designed for meteorological observations, started systematic earth observations from space from 1, April, 1960 (D) All of these
D
Pick up the correct statement from the following: (A) The minimum frequency of light for which no electrons are emitted, is called threshold frequency (B) Polarisingangleofglassis57.5° (C) At the polarising angle, the reflected and refracted rays are orthogonal (D) All the above
D
Pick up the correct statement from the following: (A) The surface defined by the locus of points having same phase, is called a wave front (B) The wave whose surface of constant phase are parallel planes, is known as a plane wave (C) The relative phase difference between the waves is important and not the absolute phase of a point on the wave (D) All of these
D
Pick up the correct statement from the following: (A) Topology describes the geometric characteristic of objects which do not change under transformations and are independent of any coordinate system (B) Topological characteristics of an object are independent of scale measurement (C) The three elements of topology are adjacency, containment, and connectivity (D) All of these
D
Pick up the correct statement from the following: (A) When the electric field oscillates in the direction of the electric vector, a plane polarised wave is formed (B) When the electric vector is in the plane of incidence, vertical polarisation is formed (C) When the electric vector is at right angles to the plane of incidence, horizontal polarization wave is formed (D) All of these
D
Pick up the correct statement from the following: A. Phytoplankton contains photosynthetically active pigment B. An increase of phytoplankton increases the back scattering in the green region C. An increase of phytoplankton absorbs the bule region rapidly D. An increase of phytoplankton decreases the back scattering in the green region
D
Pick up the important characteristic of a target which facilitates its identification from the following: (A) Spectral variation (B) Spatial variation (C) Temporalvariation (D) All of these
D
Repetitive observations of the same area at equal interval of time are useful to monitor the dynamic phenomena: (A) Cloud evolution (B) Vegetative cover (C) Snow cover(D) All of these
D
Spatial variation in horizontal and vertical directions is caused due to: (A) Physical weathering of rocks (B) Chemical weathering of rocks (C) Biological weathering of rocks (D) All of these
D
The GPS space segment consists of Navigation Satellite Timing and Ranging whose number is: (A) 8 (B) 12 (C) 16 (D) 24
D
The basic requirement of any sensor system is: (A) Radiometric resolution (B) Spatial resolution (C) Spectral resolution (D) All of these
D
The code based GPS receivers are generally used for: (A) Vehicle tracking (B) Land navigation (C) Trans movement (D) All of these
D
The object of photo-interpretation is: (A) Identification (B) Recognition of objects (C) Judging the significance of objects (D) All of these
D
The object of photo-interpretation is: A. Identification B. Recognition of objects C. Judging the significance of objects D. All of these
D
The optical property of a water body depends on: (A) Absorption by the dissolved material (B) Absorption by the suspended particulate matter (C) Scattering by the suspended particulate matter (D) All of these
D
The remote sensing techniques applied for the earth's surface features, is generally confined to the following wave lengths: (A) 0.4 to 1.3, 1.5 to 1.8, 2.2 to 2.6 um (B) 2.2 to 2.6, 3.0 to 3.6, 4.2 to 5.0 um (C) 4.2 to 5.0, 7.0 to 15.0 um and 1 cm to 30 cm (D) All of these
D
Which one of the following attributes is not associated with digital maps (A) Colour (B) Symbology (C) Legends (D) South arrow
D
Which one of the following errors is produced by platform characteristics of the sensor? (A) Altitude variation (B) Altitude (C) Orbit drift (D) All of these
D
Which one of the following factors does not affect the scale of the air photographs? (A) Focal length(B) Flying height(C) Ground elevation (D) None of these
D
Which one of the following factors does not affect the scale of the air photographs? A. Focal length B. Flying height C. Ground elevation D. None of these
D
Which one of the following frequency regions is a part of sun's radiation? (A) Ultraviolet frequency region (B) Infrared frequency region (C) Radio frequency region (D) All of these
D
Which one of the following geometric errors of satellite sensors is random? (A) Scan skew (B) Panoramicdistortion (C) Earth rotation (D) Altitude variation
D
Which one of the following parameters is considered to determine the reflectance of a vegetation canopy? (A) Solar zenith angle (B) Azimuth angle(C) Look angle(D) All of these
D
Which one of the following quantities forms the basis of radiometry? (A) Radiant energy (Q) (B) Radiant flux ( ) (C) Radiant intensity (I) (D) All of these
D
Which one of the following quantities forms the basis of radiometry? A. Radiant energy (Q) B. Radiant flux ( ) C. Radiant intensity (I) D. All of these
D
Which one of the following residual biases involves the GPS accuracy? (A) Satellite dependent biases due to uncertainty in the orbital parameters of the satellite (B) Receiver-dependent biases due to clock stability with line (C) Signal propagation biases due to the sphere and troposphere propagation (D) All the above
D
Which one of the following statement is correct? (A) Radiant energy expressed in Joules, is the energy associated with electromagnetic radiation (B) The rate of transfer of radiant energy is called flux and is expressed in watts (C) The radiant energy which falls upon a surface is termed as irradiance (D) All of these
D
Which one of the following statement is correct? A. Radiant energy expressed in Joules, is the energy associated with electromagnetic radiation B. The rate of transfer of radiant energy is called flux and is expressed in watts C. The radiant energy which falls upon a surface is termed as irradianceD. All of these
D
Which one of the following statement is incorrect regarding the electromagnetic radiation? (A) These are produced by the motion of electric charge (B) The oscillation of charged particles sets up changing electric fields (C) The changing electric fields induce the changing magnetic fields in the surrounding medium (D) None of these
D
Which one of the following statement is incorrect regarding the electromagnetic radiation? A. These are produced by the motion of electric chargeB. The oscillation of charged particles sets up changing electric fields C. The changing electric fields induce the changing magnetic fields in the surrounding medium D. None of these
D
Which one of the following statements is correct regarding the GPS satellites? (A) The nominal altitude is about 20,200 km (B) The inclination of axis satellite is 55° (C) The satellite transmits two L band signals (L1 with 1575.42 MHz and L2 with 1276.6 MHz) (D) All of these
D
Which one of the following statements is correct? (A) During the day, earth reflects solar radiation (B) During the day, earth reflects both solar radiations the emission from its surface (C) During the night, earth emits radiation from its surface (D) All of these
D
Which one of the following statements is correct? (A) Snow albedo falls at all wave length with the increase of grain size (B) The effect of grain size on reflection is maximum in the near-IR region (C) The effect of grain size on reflection is low in the visible region of the spectrum (D) All of these
D
Which one of the following statements is correct? (A) The function of an information system is to improve one s ability to make decisions (B) The information system is the chain of operations (C) A map is a collection of stored, analysed data, its stored information is suitability used in making decisions (D) All the above
D
Which one of the following statements is correct? (A) pi (pi symbol) radians equal to 180 degrees (B) The cone subtended by an area on the sphere at the centre, is called the solid angle (C) The solid angle is equal to the ratio of the area on the sphere and the square of the radius of the sphere (D) All of these
D
Which one the following is a correct statement? (A) The vertical section of the soil extending into the parent material, is called profile (B) The layers of the soil parallel to the earth surface are called horizons (C) The transitional layer between two adjoining horizons is called boundary (D) All of these
D
ick up the correct statement from the following: (A) Frequency is the number of wave crests passing a fixed point in one second (B) Frequency of a wave is measured in Hertz (Hz) (C) Amplitude of a wave is the height of its crust from the mid-point (D) All of these
D
Pick up the correct statement from the following: A. The minimum frequency of light for which no electrons are emitted, is called threshold frequency B. Polarising angle of glass is 57.5° C. At the polarising angle, the reflected and refracted rays are orthogonal D. All the above
D. all of the above
Leaf reflactance depends primarily on : A.the pigments B.internal cell structure C.equivalent water content D.All of these
D.All of these
Water surfaces in images record ....... areas in the near infrared channel:
Dark
Match the scattering to the phenomenon/application. Debye Raman Compton Rayleigh
Debye- white clouds Raman- spectroscopy Compton- x-ray photographs Rayleigh- blue sky
Resampling of a raster image:
Decreases data details
Spatial Resolution
Describes the area on the Earth represented by a pixel
What parts of earth would have the highest albedos?
Deserts
An analyst uses a database management system to copy selected records from two source files into a new destination file. Which of the following operations selects only those records that appear in one, but not both, of the source files?
Difference
The use of computer algorithms to perform processing on digital images is called:
Digital image processing
It is easy to integrate GIS, Remote Sensing and GPS technologies because these are:
Digital, spatial and generic
The unit of measurement for corrective lenses is called_______________.
Diopters
Depicted below is a picture of a 22° halo around the moon. Note that the colors of the rainbow can be seen in the halo. The current, standard hypothesis for the formation 4 of the halo states that the interaction of light with ice crystals in the atmosphere produces the natural phenomenon. State the physical process responsible for the formation of the halo.
Dispersion, and Refraction
RGB colour scheme is used for:
Display
Why do the edges of a vertical photograph get distorted?
Distortion due to distance
___ radar, as often used for precipitation radars, can detect motion of rain droplets or other precipitation
Doppler
Pick up the correct statement from the following: A.In remote sensing technique, the observation place, is called a platform B.Platforms may be either stationary or mobile C.Spatial resolution of the imaging system becomes poorer with increase of platform height. D.Area coverage of the imaging system increases with the increase of the platform altitude. E.All of these
E.All of these
What was the Terra satellite originally known as?
EOS AM-1
_____ is a remote sensing software
ERDAS IMAGINE
The first microwave remote sensing satellite was:
ERS-1
Which space-borne satellite programme has a goal of improving our understanding of the Earth-Sun system and its response to natural and human induced changes?
Earth Observing System
Inclination is the angle of the orbit of a satellite in relation to
Earth's Equator
Which of the following can travel through empty space?
Electromagnetic waves
Which one of the following can travel through empty space?
Electromagnetic waves
Which of the following can be accomplished using LiDAR technology? Select all that apply. Elevation measurements Calculating rock density Obstacle detection Calculating height of vegetation Quantum-mechanical observations
Elevation measurements Obstacle detection Calculating height of vegetation
Pixel Purity index is used for identifying __?
End member
Specular Reflection
Energy is deflected in a single direction
Diffuse Reflection
Energy is reflected in all directions
In the process of image classification, which of the following methods results in a greater accuracy of classes within an image actually matching land use patterns on the ground?
Manual/supervised by a user
Which of the following is an area of Remote Sensing application?
Mapping and water resources
Which physicist has a black body radiation law named after him?
Max Planck
Who first described the color additive theory?
Maxwell
Filter that replaces pixel value with medians of intensity levels is
Median filter
A satellite with an orbital period of three hours has what type of orbit
Medium Earth orbit
A 1:50,000 scale map can be compared to the following spatial resolution:
Not possible to compare
Which one of the following parameters is considered to determine the reflectance of a vegetation canopy
Number and arrangement of leaves
The main difference between multispectral and hyperspectral is the ___ of bands and how ___ the bands are:
Number, narrow
What is the order of the A-train satellites as they appear over the equator each day?
OCO-2, GCOM-W1, Aqua, CloudSat, CALIPSO, Aura
Image can have only ................integer pixel values, whereas grid can have ................. and .................real and ...............cell values.
Positive, Positive, Negative, Integer
What are the differences between a spectrometer and a radiometer? a. A spectrometer are standalone systems that are highly accurate in analyzing multiple spectral ranges b. A radiometer are much more simple and only measures a specific wavelength range c. A spectrometer are not standalone and require a set of optics to correctly work Two of the Above None of the Above
Two of the above
Which one of the following frequency regions is a part of sun's radiation?
Ultraviolet frequency region, Visible frequency region, Infrared frequency region
An orthophoto is useful because of its:
Uniform scale