What causes a rainbow?

Answer 1

Sunlight passing through the moisture in the air.

Answer 2

For a rainbow to be seen, the observer needs to be between the Sun and an area of airborn water drops. This can be a rainfall, a waterfall or a garden sprayer. The size of the drops of water is not important The angle of the light is important. If the sunlight cannot be reflected at an angle of about 23 degrees into your eyes, you will miss the rainbow. You can only see them from the ground in the morning or afternoon, never midday.

The water acts like a prism, allowing light in on one side, bouncing it off the other side and back out the first side. But water has a refractive index, bending the light. Higher energy frequencies at the violet end of the spectrum are bent less than the lower frequencies at the red end. So you see a spread of all the colors instead of all white. If conditions are right, you might see a second, dimmer, echo rainbow, with reversed colors at the 46 degree angle.

You might see a rainbow in midday if you are flying over a cloudbank and the sun is behind you. It will be a full circle because there isn't any ground to obscure the effect. The "ends" of ground rainbows are merely the point at which there aren't enough water droplets to maintain the effect. If you try to "go" there, the rainbow will move away or fade because your viewing angle has to remain 23 degrees. You'll be seeing the rainbow through different drops, until there aren't enough drops in front of you to shine against background light.

It is even possible to see a rainbow at night, using moonlight, but this is extremely rare. The moon has to be bright enough and at the right angle, and the rain has to be heavy enough or you won't see it at all. It will be very dim and nearly colorless. There are several nice time exposure "moonbows" on the web. (They'll look colorful but there will be stars in the sky.)

Answer 3

When light passes from air into water (or glass), or water into air, different colors are refracted (bent) a different amount. Red is refracted the least, and violet the most. And so, the colors are separated into a spectrum, or rainbow. When raindrops are in the air, most light is either reflected off of the drops or goes right through them. If the light enters at certain angles, the light enters the drop, is reflected inside, and then exits the drop. Entering and exiting the drop, the colors are separated. You see red light come from a raindrop because that drop is at just the correct angle (about 42 degrees) between your eye and the sun so that the red light coming from the sun is refracted, reflected, and refracted again right into your eye. Blue light comes from another raindrop at a slightly different angle. All the raindrops that are at a certain angle between your eye the sun form a circle in the sky. That is why the rainbow is a circle.

Answer 4

Good question. When this happens, when you see a rainbow, you are standing between the Sun and the rainbow, with rain between you and the rainbow. The sunlight comes from behind your back and is reflected from the drops of rain in the direction of the rainbow and back to your eyes. The rain drops separate the white light of the Sun into its separate colors violet through orange and red. This is called refraction. Check this out the next time you see a rainbow. Look to see where you are, where the sun is, and where the rainbow is. Ok?

Answer 5

Rainbows are created when sunlight shines through tiny water droplets that are suspended in the air. A rainbow occurs when there is rain in one portion of the sky. Did you know rainbows are only light? Rainbows get their name from their shape. Isaac Newton is the scientist who explained the rainbow. Did you know a rainbow is not physical? We see rainbows because the sun splits them into 7 colors.

Answer 6

Rainbows are seen when raindrops, falling in the distance, bend and bounce sunlight back towards your eye.

Raindrops reflect sunlight, like a mirror. However raindrops also bend, or refract, light, like a lens. The reflection is spread into a cone of light. The edge of this cone is bright, because sunlight is concentrated at this angle (called the rainbow angle).

Each colour of sunlight is bent and bounced in a slightly different direction. The colours separate around the bright edge of the reflection.

The collection of raindrops that send the same bright colour towards your eye is curved. The centre of the curve is the shadow of your head (called the anti-solar point). The rainbow always appears at the same distance from this central point, at the rainbow angle.

the tiny water paticles act as prism to the lgiht and cause it to spread into 7 colours...all the coulours in d world are formed out of these 7 colours seriously..........take care

Answer 7

Most importantly Rainbow is only a visual effect that can be seen only in the Mornings Or Evenings. Never during Mid Day. No Rainbow if it is pouring down!

Answer 8

Although light looks colorless, it’s made up of many colors-red, orange, yellow, green, blue, indigo and violet. These colors are known as the spectrum. When light shines into water, the rays of light refract, or bend, at different angles. Different colors bend at different angles--red bends the least and violet the most. When light passes through a raindrop at a certain angle, the rays separate into the colors of the spectrum-and you see a beautiful rainbow..

Answer 9

it is caused by sunlight refracting off of water droplets at a certain angle. The sun and the water droplets have to be at the perfect angle for you to see it. I can't remember but I thought I remeber someone telling me it has to be a 60 degree angle that the light hits the drops of water.
the water droplets bend the light and make all the colors of the sunlight visible to us.

Answer 10

the reflection of Ultraviolet rays off of a downdraft of storms typically. However, rainbows can form from the ultraviolet rays reflecting off Ice crystals inside cirrus clouds.