Astronomy test 3
absorption
a low density, cool gas in front of a hotter source of a continuous spectrum creates a dark line or a...? its the suns atmosphere
temperature
cannot tell luminosity without what
doppler shift
caused by "radial" motion. there will be a shift in the spectral lines of an object if it is moving.
acceleration
change in speed change in direction
force decreases
distance increases
energy at all wavelengths
each object outputs
x-rays and gamma rays
earths atmosphere completely blocks
radio waves, visible light
earths atmosphere lets through
infared and UV
earths atmosphere partially blocks
luminosity
energy output over the entire star
microwave
a grain of sugar is about the same size as the wavelength of...
radio wave
A mountain (1km) is about the same size as the wavelength of...
continuous
A solid glowing hot object will emit light over the full range of wavelengths resulting in a ____________________ spectrum.
E
An important line in the absorption spectrum of stars occurs at a wavelength of 656nm for stars at rest. Imagine that you study five stars (A-E) from Earth and discover that this absorption line is observed at the wavelength shown in the below for each of the five stars. Which star is moving the fastest toward the observer?
Slow towards us: Star A, Fast towards us: Star E
An important line in the absorption spectrum of stars occurs at a wavelength of 656nm for stars at rest. Imagine that you study five stars (A-E) from Earth and discover that this absorption line is observed at the wavelength shown in the below for each of the five stars. Which stars are moving the fastest towards us?
X-ray wavelengths are longer compared to gamma rays
How do X-ray wavelengths compare to gamma ray wavelengths?
Infrared photons have less energy compared to ultraviolet photons
How does the energy of infrared photons compare to ultraviolet photons?
Infrared light has the same speed compared to microwave light
How does the speed of infrared light compare to microwave light?
absorption spectrum
If a diffuse (low density) and relatively cool cloud of gas is located between a glowing hot object and an observer, what type of spectrum will the observer detect?
absorption
If the Hubble Space Telescope were looking at a distant star, the light from that star would produce which type of spectrum?
Greatest A D B C Least
Imagine you are comparing four electric hot plates (A - D) of different sizes and temperatures. The temperature of each hot plate is indicated by a shade of gray such that the lighter the shade of gray, the higher the temperature of the hot plate. Rank the total energy output or luminosity (from greatest to least) of the hotplates.
A
In the above picture, the starship's probe sends a pulse which contains all bands of the electromagnetic spectrum in a uniform amount. Which is the graph of the pulse sent from the spaceship.
Radio Waves
Longest wavelength, lowest energy, and lowest frequency
Very Large Array
New Mexico, more telescopes=more detailed, radiowaves things (VLA)
black body curve
a curve of their radiation at all wavelengths is called
D
Shown are four absorption line spectra of stars. The short-wavelength (blue) light is on the left-hand side of the spectrum, and the long-wavelength (red) light is on the right-hand side. Which of these stars is moving the fastest toward the observer?
C
Shown are four situations (A-D) where two asteroids are near each other (d=distance, m=mass). Which of these has the weakest gravitational force between them?
F
Star A and F are the same brightness. Which star is bigger?
decreases and the peak shifts to the right
The blackbody curve for an object at T = 2,000 K is shown in the figure. For an object of the same size, if the temperature is lowered to 1,500 K the area under the curve
increases and the peak shifts to the left
The blackbody curve for an object at T = 2,000 K is shown in the figure. For an object of the same size, if the temperature is raised to 2,500 K the area under the curve
blue
The blackbody curve for an object with a temperature of 30,000 K is shown. To an observer, this object would appear
c
The figure shows the motion of four distant stars (A - D) relative to a stationary observer (telescope). The speed and direction of each star is indicated by the length and direction of the arrows shown. In addition, their spectra (1 - 4) as seen from Earth are shown. Assume that the left end of each spectrum corresponds to shorter wavelengths (blue light) and that the right end of each spectrum corresponds with longer wavelengths (red light). Which star is Spectrum 3?
Moving fastest toward A C D B Moving fastest away
The first spectrum shown below is of an element as it appears in a laboratory here on Earth. In addition, the spectra of four stars (A - D) as seen from Earth are shown. Assume that the left end of each spectrum corresponds to shorter wavelengths and that the right end of each spectrum corresponds with longer wavelengths. Rank the speed of the stars from moving fastest toward the Earth to moving fastest away from Earth.
c
The first spectrum shown below is of an element as it appears in a laboratory here on Earth. In addition, the spectra of four stars (A - D) as seen from Earth are shown. Assume that the left end of each spectrum corresponds to shorter wavelengths and that the right end of each spectrum corresponds with longer wavelengths. Which star is moving away from us the fastest?
b
The first spectrum shown below is of an element as it appears in a laboratory here on Earth. In addition, the spectra of four stars (A - D) as seen from Earth are shown. Assume that the left end of each spectrum corresponds to shorter wavelengths and that the right end of each spectrum corresponds with longer wavelengths. Which star is moving towards us the fastest?
D
The graph illustrates blackbody curves for different stars. Which of the stars has the lowest surface temperature?
a
The graph illustrates blackbody curves for different stars. Which of the stars is the smallest?
absorption spectrum
The observer viewing with the perspective of the arrow in the diagram would see a(n)
star b
The three spectral curves shown illustrate the energy output versus wavelength for three unknown stars A, B, and C. Which of the stars is giving off the most Energy Output per second?
continuous
What type of spectrum is produced by the inner hot layer of the photosphere of a star?
absorption line
What type of spectrum would you see if you use a telescope to collect light from a star and spread it out with a prism?
Neither graph
Which of these graphs shows Stars A and B correctly?
more mass
less acceleration
more acceleration
less mass means more what
lower the frequency and energy
longer the wavelength...
redshift
longer wavelength, star moving away from observer
red
longest wavelenght color
energy
proportional to frequency
higher the frequency and energy
shorter the wavelength...
blueshift
shorter wavelength, star moving twoard observer
violet
shortest wavelenght color
Speed of light
speed of electromagnetic radiation
blackbodies
stars can be approximated as
velocity
the higher the ... of the star (or observer), the greater the shift
red
what color is coolest
temp and color
the peak wavelength of a blackbody curve tells us about the objects?
blue
what color is hottest
E
which star is giving off the lowest energy output
The gravitational force between his spacecraft and Earth would be two times the gravitational force between my spacecraft and Earth
In the picture, the Earth-Moon system is shown (not to scale) along with five possible positions (A - E) for a spacecraft traveling from Earth to the Moon. Note that position C is exactly half-way between Earth and the Moon. Imagine you have a space craft at position A and Carl Sagan had a spacecraft that is two times the mass of yours, but at the same distance from Earth. How would the gravitational force between Earth and his spacecraft compare to the gravitational force between Earth and your spacecraft?
The gravitational force would be the same
In the picture, the Earth-Moon system is shown (not to scale) along with five possible positions (A - E) for a spacecraft traveling from Earth to the Moon. Note that position C is exactly half-way between Earth and the Moon. Imagine you have a space craft at position E and Wayne Gretzky had a spacecraft that is ten times as big, but the same mass as yours and at the same distance from the Moon. How would the gravitational force between the Moon and his spacecraft compare to the gravitational force between the Moon and your spacecraft?
Greatest E, D, C, B, A, Least
In the picture, the Earth-Moon system is shown (not to scale) along with five possible positions (A - E) for a spacecraft traveling from Earth to the Moon. Note that position C is exactly half-way between Earth and the Moon. Rank (from greatest to least) the strength of the gravitational force at positions A - E exerted by the Moon on the spacecraft.
The gravitational force between the spacecraft and Earth would be stronger than the force between the spacecraft and the Moon, so the spacecraft would move toward Earth
In the picture, the Earth-Moon system is shown (not to scale) along with five possible positions (A - E) for a spacecraft traveling from Earth to the Moon. Note that position C is exactly half-way between Earth and the Moon. What would happen to a spacecraft at position C?
Red
The blackbody curve for an object at T = 2,000 K is shown in the figure. If the temperature was decreased to 1,500 K, what color would it appear to be?
Light waves
wavelength, frequency, and energy define what
Continuous (rainbow)
If a star existed that was only a hot, dense core and did not have a low-density atmosphere surrounding it, which type of spectrum would you expect this particular star to give off?
Dark Line absorption spectrum
Imagine that you observe the Sun while in your space ship in orbit around the Moon. Which of the following spectra would you observe by analyzing the sunlight?
Less than between a person standing on the Earth and the Earth
How strong is the force of gravity between a person standing on the Moon and the Moon?
Greatest A, B, C, D, E, Least
In the picture, the Earth-Moon system is shown (not to scale) along with five possible positions (A - E) for a spacecraft traveling from Earth to the Moon. Note that position C is exactly half-way between Earth and the Moon. Rank (from greatest to least) the strength of the gravitational force at positions A - E exerted by the Earth on the spacecraft.
UV
molecules are about the same size as the wavelength of...
An atomic nucleus
The wavelength of a gamma ray is about the size of
an atomic nucleus (.00001 nm)
The wavelength of gamma rays is about the size of...
light that was absorbed by a cool low-density cloud
When viewing an absorption spectrum, the dark lines you see represent what?
Absorption
Which kind of spectrum would the setup above produce?
A
Which of the following has the largest wavelength?
A
Imagine you are comparing four electric hot plates (A - D) of different sizes and temperatures. The temperature of each hot plate is indicated by a shade of gray such that the lighter the shade of gray, the higher the temperature of the hot plate. Which hotplate is giving off the highest amount of energy (which is the most luminous?).
Gamma Rays
Shortest wavelength, highest energy, highest frequency
Strongest B, D, A, C, Weakest
Shown are four situations (A-D) where two asteroids are near each other (d=distance, m=mass). Rank the gravitational force between the objects from strongest to weakest.
Strongest C B A D Weakest
Shown are four situations (A-D) where two asteroids are near each other (d=distance, m=mass). Rank the gravitational force between the objects from strongest to weakest.
C
Shown are four situations (A-D) where two asteroids are near each other (d=distance, m=mass). Which of these has the strongest gravitational force between them?
Hubble
Telescope, 1990-current, low earth orbit (we can reach it through astro) UV, Visible, IR, Orbits earth mirrors
SOHO (Solar observatory)
telescope, 1995-current, faces the sun, orbits the sun, wavelengths: UV extreme UV reflecting telescope mirror
temperature
the "pattern" of radiation depends on the
It was absorbed by cooler gasses in the outer part of the star
There are dark lines in the absorption line spectrum. What happened to this light that is missing in the absorption line spectrum?
Earth based observing problems
These problems effect what: Earths atmosphere blcoks some form of light, turbulence in earths atmosphere causes bluring/twinkling more water=more twinkling, light pollution, weather predictability
Infared
Typical stars (like our 6000 K Sun) produce most of their light in the visible band of the EM spectrum and are best observed in that band. Which of the bands below would be most useful for observing clouds of hydrogen in between stars with temperatures around 20 K?
A
Which of the following bands of the electromagnetic spectrum has photons with the highest frequency? A. X-rays B. All bands of the electromagnetic spectrum have the same frequency C. visible D. microwave
a
Which of the following bands of the electromagnetic spectrum has photons with the highest frequency? a) x-rays b) all band of the electromagnetic spectrum have the same frequency c) microwave d) visible
A
Which of the following bands of the electromagnetic spectrum has photons with the lowest frequency? a) microwave b) all bands of frequency have the same frequency c) x-ray d) visible
C
Which of the following has the shortest wavelength?
C
Which of the following pairs of masses exerts the largest gravitational force on each other?
D
Which of the following pairs of masses exerts the largest gravitational force on each other?
B
Which of the following pairs of masses exerts the smallest gravitational force on each other?
C
Which of the following pairs of masses exerts the smallest gravitational force on each other?
Microwave (or Radio)
Which of the following photons in the electromagnetic spectrum has the largest wavelength? A. x-rays (or gamma rays) B. all of these choices have the same wavelength C. Microwave (or Radio) D. Visible (or UV or IR)
B
Which of the following photons in the electromagnetic spectrum has the largest wavelength? a) Visible (or UV or IR) b) Microwave (or Radio) c) All of these choices have the same wavelength d) X-rays (or Gamma-Rays)
The first graph
Which of these graphs show Stars A and B correctly?
The second graph
Which of these graphs shows Stars A and B correctly?
Star F
Which star has the lowest surface temperature?
F
Which star looks red
Emission
Which type of spectrum is produced by the setup shown above?
Continuous
Which type of spectrum would be produced by the setup shown above?
Chandra Observatory
X-ray
up and down
there is no doppler effect when the star moves ... relative to the observer
visible
a piece of bacteria is about the same size as the wavelength of...
infared
a protozoan is about the same size as the wavelength of ...
Wavelength
all have same speed
X-rays
an atom is about the same size as the wavelength of
greater shift
faster moving means greater or lower shift
radio waves, visible and some infared and UV
ground based telescopes can observe what wavelengths
continuous
hot dense source, light bulb, rainbow, molted rock, lava, a luminous solid, liquid, or dense gas emites light @ all wavelengths and produces a what? complete rainbow of colors no gaps of bright lines
emission
hot dilute gas, neon sign, gas bulbs/tubes, a low density, hot gas in front of a cooler background emits a bright line or a...? hot diffuse so atoms more spread out
more energy at all wavelenghts than a cooler object
hotter objects output
their maximum energy at shorter wavelengths
hotter objects output
frequency
how many curves travel in 1 second, # of peaks that pass a fixed point in one second (hertz)
the force due to gravity decreases
if the force is greater
force
if the mass increases then what also increases
surface area and temperature
luminosity depends on
spectrum
measurement of light from an object over a range of wavelenghts
