Colors Physics

Light travels

As a stream of particles (transverse electromagnetic radiation) / wavicles

Refraction

Bending because part of wave slow down or speeds up

Blue color in a darkroom with red light

Black (no color to reflect)

Complement of red

Cyan

White - red

Cyan (complement of red)

Polarizing filter

No light through if you combine a horizontal filter with a vertical filter

Diverging

Spreading apart.

Red + green + blue

White

Red stripes in a darkroom with red light

Will be red

White stripes in a darkroom with red light

Will be red

Complement of blue

Yellow

Red + green

Yellow

White - blue

Yellow

Green + blue

cyan

What color would a red rose be if it was under a blue light (why)?

A red rose would be black under a blue light because if a white light shone on a red rose all the other colors would be absorbed and only red would be reflected making the rose red. This means that a red rose would absorb blue light. Therefore if only blue shown on a red rose, the blue would be absorbed and the rose would be black since there is no red to be reflected.

Why are clouds white?

Clouds are white because when light interacts with water molecules it scatters. Some of the waters droplets are so big that they won't vibrate and let the light through but instead they absorb the light. Bigger droplets scatter lower frequencies of light (red) and smaller water droplets scatter higher frequencies of light (violet). As the light from the sun gets absorbed by the water droplets, the water droplets as a whole create white light. Therefore, this white light make the clouds look white in the sky when you look at them.

Reflection

Flipping a figure to produce a mirror image.

Mix paint

Getting less color - black

Mix light

Getting more color - white

Why do great white sharks look cyan under 50 feet of water?

Great white sharks look cyan under 50 feet of water because red light does not reach that far down in the ocean. Red light can be aquated to heat because of its low frequency. Therefore red cannot reach that far down in water since it gets taken out right away. On land the white shark would reflect white in white light. However without the color red being able to reach the shark, the shark reflects cyan. Cyan is a makeup of both green and blue which do reach the shark. Therefore, the shark would look cyan under 50 feet of water.

Sun naturally

Horizontally polarized so polarizing lenses are oriented vertically

Diffraction

Occurs when a ray of light bends around the edges of an object.

Why is the sky blue?

The sky is blue because sunlight (white light) contains all the colors of the visible light spectrum and they interacts with the oxygen and nitrogen in the atmosphere. When they interact the violet light scatters the most because violet light has the highest energy and therefore the highest frequency of visible light on the electromagnetic spectrum. The violet light would be scattered the most across the sky. However, after violet the second most scattered light is blue and then green and so on. Violet, blue and green scatter most across the sky but these colors average out to be blue. Our eyes are more accustomed to seeing blue than violet, so the sky looks blue.

white - blue

Yellow (Complement of blue)

What color would make a green dress look black at a Halloween party (why)?

If you shine white light on a green dress it would reflect green and absorb all other colors. When green if reflected from the dress, it also contains yellow and blue. All these colors average out so it looks green but is also composed of yellow and blue. If you shine a yellow light on the green dress, yellow would be reflected. Also if you shine a blue light on the green dress, blue would be reflected. This is the same with the green light. However, if you shine a red light on the green dress it would seem black. Red is only composed of red and orange and a green dress only reflects green, blue and yellow light. Hence the dress would look black because the green dress would not reflect red or orange from the red light.

Complement of green

Magenta

blue + red

Magenta

Why is the sun an orangish red at sunset?

The sun is an orangish red at sunset because when light from the sun creates reaches the earth at an angle, it has to travel through much more atmosphere. This makes the light scatter more before it reaches a person experiencing an orangish red sunset. The violet and blue light would have already been mostly scattered in the sky by the time the light reaches the person. The higher frequencies of light (violet and blue) interact with particles more which causes them to scatter more. Red light scatters the least and violet scatters the most light. Therefore the person can see other lights with lower frequencies better at a sunset because they are not scattering as much as violet and blue light. These lower frequency colors average out to be a orangish red so that what you see in the sky.

Blue dress not be blue

Use orange light

If you look at the blue sky through a yellow filter what color would you see (why)?

You would see green because only green makes it through the filter. It is not pure blue light that reaches the filter but composed of blue, violet and green. All these colors average out to create blue light, so that's why it looks blue. When the blue, violet and green light try to get through the yellow filter, the yellow filter only lets through yellow light and absorbs all other colors. However the yellow light is composed of orange and green. Green from the blue sky tries to make it through and the yellow filter lets its through. Therefore the filter would look green. If this was a perfect filter and only let through yellow, you would just see black.

Converging

coming together at a point