How do rainbows form?

Answer 1

Sunlight is made up of the colours of the rainbow, though we don't normally see the separate colours. When sunlight passes through raindrops in the sky, the raindrops can act like a clear glass prism. This prism effect splits the sunlight into the colours we see in a rainbow.

Answer 2

A rainbow is an optical and meteorological phenomenon that causes a spectrum of light to appear in the sky when the sun shines onto droplets of moisture in the Earth's atmosphere. They take the form of a multi-coloured arc, with red on the outer part of the arc and violet on the inner section of the arc.

After the rain, small water particles are dispersed in the air. As the sunlight (white light) consists of seven colors, so when it passes through the water droplets, they are split up

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By Sandy!!,MHJC
Rainbows are made when light is refracted through millions of droplets in the air. White light is made up of red, orange, yellow, green, blue and violet light, so when it is split into components by the water droplets, it is seen as a rainbow.

Rainbows usully occur when the moisture in the air, such as after a rainstorm, when the sun is out.

it also occurs in waterfalls and ocean waves.
Rainbows are caused by the refraction of sunlight in millions of raindrops. The sun must be behind you and quite low for a rainbow to occur. This is why they're never seen in the middle of the day. Sometimes, if the light has been refracted twice inside each raindrop a second fainter one can be seen about 9 degrees outside the first. The colours on the outside are reversed in order, red being in the inside.

A rainbow is actually a spectacular natural optical illusion.

Individual raindrops act like tiny prisms, splitting the white light from the Sun (or other white light source) into a continuum of different hues, from deep violet to deep red.

From any given point BETWEEN the Sun and the rain droplets, a single droplet would appear to refract a tiny speck of light in one particular hue, depending on its position.

However, billions of raindrops combine their refractions to form the whole image.

If one were to draw a straight line from the Sun to the Observer, then project that line straight along, it ALWAYS points to the very center of the circle (or arc) formed by the rainbow. Since the ground usually interferes with a complete image, one almost always sees just an arc. High in the mountains, however, the arc continues further around towards a circle.

The colors of the rainbow are always the same - starting from the outside: red, orange, yellow, green, blue, indigo, violet.

The reason it is IMPOSSIBLE to approach one end of the rainbow is that the rainbow illusion simply recedes as the viewer travels toward it.
Rainbow is formed when light from a distant source usually the Sun falls on a collection of water drops such as in rain, spray, or fog.