What is a Rainbow?

Whenever a rainbow appears in the sky it is a meteorological phenomenon, which can be characterized as a multicolored circular arc. It is created by the dispersion of light in water droplets. The refraction and reflection of light from the droplets are the primary factors that give rise to the phenomenon.

Primary rainbow

Generally, a rainbow is a concentric circular arc of many colours in the sky. They are formed by light rays from raindrops striking the air, and are best seen in the early morning hours. However, rainbows can also be seen around waterfalls or fog.

A rainbow has many colours, including red, orange, green, blue, and yellow. Each colour contributes to a different part of the rainbow, such as the middle. Some of the colours have more than one minimum deviation angle, which gives the rainbow its colours.

There are three different types of rainbows: the primary, secondary and supernumerary. The primary rainbow is the most common type, and is formed by light rays striking a raindrop at an angle of 42 degrees from the shadow of the sun.

Refraction of sunlight on a raindrop

Using the laws of reflection and refraction, sunlight striking a raindrop will break up into seven different colors. These colors include red, yellow, blue, green, and violet.

There are several reasons why light refracts. Some of the reasons include the differences in optical density between water and air. These differences are illustrated by the following diagram.

The angle that the light strikes the raindrop determines how much of the light is refracted. Red light is refracted at a steeper angle than blue light.

In addition, the size and shape of the raindrop determine how much light is refracted. Small raindrops are more spherical and refract light more efficiently than larger droplets. However, small raindrops are also more prone to being distorted by air turbulence.

Reflected rainbows

Depending on the conditions, reflected rainbows can appear in lakes, rivers, or the ocean. They can also occur over a puddle or small body of still water.

These rainbows are formed by light waves that travel through water droplets. Light rays reflect off the droplets and spread out into a field. The refractive index of water droplets determines the radius of the rainbow. Water droplets with high refractive index will produce a smaller rainbow.

Full circle rainbows are rare because the raindrops must be below the horizon. However, they can be seen from the top of a mountain or high skyscrapers.

Primary rainbows are created when sunlight reflects off of a smooth surface. They are usually red, and usually seen during sunrise and sunset.

Refractive index of the glass causes dispersion of colors in a prism

Whenever light passes from one medium to another, it is refracted. A prism is an optical device that splits light into different colors. This is done by ordinary glass. It also creates the rainbow effect.

When white light passes through a glass prism, it is split into spectral components. The refractive index of the glass is what causes the light to be refracted. The refractive index of the glass changes with the wavelength of the light. The higher the refractive index, the more the light is refracted. The longer the wavelength, the smaller the index. The index of refraction also changes with the speed of the wave.

There are several materials with different refractive indices. Some materials have a stronger dependence on wavelength. For example, the refractive index of glass is 6 degrees higher than that of water.

Experiments to study the nature of rainbows

Using rainbow science experiments, you can explore the way different colors are refracted by water droplets. Rainbows are formed from trillions of small raindrops floating in the air. When the light from the sun passes through these droplets, it produces a rainbow. These rainbows are commonly seen during the summer months.

A rainbow can be produced by spray, mist, and airborne water such as rain and dew. These water droplets act as tiny prisms, refracting the light into a rainbow. Each droplet of water has a different refractive index. Consequently, the light refracts in different amounts when it enters the droplet and refracts again when it leaves.

The size of a rainbow depends on the size of the droplets. Small raindrops produce almost white rainbows, while large raindrops produce bright rainbows.