Mod3

the angle of incidence ____ = angle of reflection ______

(30*), (30*)

light travels at _________ m/s

186,000 m/s

Light travels at

300,000 km/s

Red light has a wavelength of ____ while violet has a wavelength of __

700 nm, 400 km

how many minutes does sun need to reach the Earth?

8 minutes

who is the Arab scientist that said the eyes simply collect the light that falls into them?

Alhazen

Closest star to earth is ______. It is over ________ away from Earth

Alpha Centauri, 4.24

all ABSORBED is _______ while all REFLECT is _______

Black; White

Who first proposed the Wave Theory of Light and believed that light was made up of waves vibrating up and down perpendicular and formulated a way of visualizing wave propagation = electromagnetic spectrum

Christian Huygens

Why is red light used in photographic darkrooms?

Darkrooms used red lighting to allow photographers to control light carefully so that light-sensitive photographic paper would not become overexposed and ruin the pictures during the developing process.

the range of all types of EM radiation.

Electromagnetic (EM) spectrum

T or F: A shadow is a dark reflection

False

T or F: Light from a candle does not travel as far during the daytime

False

T or F: Light from the sun can travel further light from a candle

False

T or F: We can only see things that are making light

False

The uninterrupted area or distance over which the wind blows (in the same direction).

Fetch

Increasing wavelength of light goes in this order:

Gamma Rays, x-rays, UV, Visible light (violet-red), infrared, microwave, radio

incident ray

Incoming ray

energy that travels and spreads out as it goes

Radiation

Who studied the interference of light waves by shining light through a screen with two slits equally separated, the light emerging from the two slits, spread out according to Huygen's principle

Thomas Young

T or F: Plato and Pythagoras thought that light originated in our eyes and that vision happens when little invisible probes were sent to gather information about far-away objects.

True

T or F: only waves make interference patterns, particles don't

True

T or F: very few objects actually emit their own light

True

used in water filtration, disinfection

UV light

why not all UV light reaches Earth.

UVB and UVC waves have more energy, they have the greatest potential to damage the skin.

The number of waves/oscillations passing a fixed point in a specified period of time

Wave Frequency

The vertical distance between the wave trough and the wave crest.

Wave Height

The time it takes for two successive crests to pass a specified point.

Wave Period

The distance between two consecutive wave crests or between two consecutive wave troughs

Wave length

If you are in a room that that is completely dark, what would you see? What happens after you wait a long, long time?

You will just see black - forever

light that is taken in and not reflected or transmitted

absorbed light

the size of the displacement for the disturbance

amplitude

4 properties of light

amplitude, wave speed, wavelength, frequency

Light waves can interfere with other light waves, ______

canceling or amplifying them

Newton believed light is made up of atom particles called

corpuscles

bending of light waves around obstacles in its path

diffraction

Fill in the blanks: Electromagnetic radiation consists of _________________, which are synchronized _______ of _________ and ________________. In a vacuum, electromagnetic waves travel at ___________, commonly denoted c.

electromagnetic waves, oscillations, electric, magnetic fields, the speed of light

what is this called: if an atom drops from one orbital to the next lower one, it must emit a photon with the same amount of energy as the orbital energy difference

emission

T or F: Wavelengths of visible light are very large

false

T or F: the angle of reflection is not the same as angle of incidence

false

shortest wavelength but the highest energy source; from radioactive material

gamma rays

The greater the fetch, the ______________ the wave height.

greater

cannot be detected by our naked eye, the heat that is easily detected, used in airports

infrared light

light makes up _____ ______ (complicated undulations that happen when two wave patterns occupy the same space)

interference patterns

the longer the wavelength, the _______ the energy

lesser

produce heat as the molecules vibrate fast

microwave

Rough surfaces/______ ______ light that's why we see colors; Smooth surfaces ______ most light

opaque, scatter, reflect

Particles of light called ____ travel through space. - These photons have very specific energies. these have specific energies that is light is ______

photons, quantized

the little invisible _____ that were sent to gather information about far-away objects

probes

an example of light as a particle: when you shine a light on metal, the light transfers its energy to the atoms in the metal in discrete packets called ________

quanta

longest wavelength ex.; bluetooth, wi-fi

radio waves

which has more longer wavelength red or violet?

red

an effect that occurs when light bends as it passes from one substance into another

refraction

Considered to be part of the brain itself, the ______ is covered by millions of light-sensitive cells, some shaped like rods and some like cones. These receptors process the light into nerve impulses and pass them along to the cortex of the brain via the optic nerve.

retina

reflected ray

the light ray that bounces off a surface

___________ materials still allow light but may konting disturbances/only some parts pass-through

translucent

__________ materials allow light to pass through without disturbances

transparent

T or F: Higher energy means higher frequency

true

T or F: Photons strike your eye (or other sensors) like a very small bullet, and are detected.

true

T or F: UV is shorter than visible light but has higher energy because it has a higher frequency

true

T or F: UV light has the shortest wavelength and higher frequency than visible light

true

T or F: because of understanding light as a wave, we also understand what color is

true

T or F: infrared light has the longest wavelength and lowest frequency

true

T or F: some experiments showed that light acts like a particle

true

T or f: cats can't see anything at all in a totally darkened room

true

T or f: light keeps travelling until it hits something

true

True or false: A lens help to form images because it bends light

true

True or false: light has to enter our eyes for us to see

true

is is true that color is not inherent in objects, thus we only perceive the reflected colors

true

for one wavelength, there must be ___ successive crests to pass a specified point

two

which has more energy violet or red?

violet

The repeating and periodic disturbance that travels through a medium (e.g. water) from one location to another location.

wave

The color of light is determined by its

wavelength

high energy, can penetrate the skin, reflected into the photographic film

x-rays