When we pass white light through a prism,
it splits into different colors
What is Dispersion?
Splitting up of white light into 7 different colors when passed through a transparent medium (like Glass Prism) is called Dispersion
When white light is passes through the prism, it splits into seven colors. They are
- V iolet
- I ndigo
- B lue
- G reen
- Y ellow
- O range
- R ed
What is Spectrum?
Band of coloured components of light are called spectrum
Hence, 7 colors formed on dispersion of light is called spectrum
What causes Dispersion ?
White light is combination of these 7 colors
When light falls on a prism, it changes medium (from air to solid)
Hence, different colors of light bend at different angles
Red light bends the least while violet line bends the most
Hence, different rays of different color emerge along different paths
This causes dispersion of light
Recombination of Spectrum to give White Light
In this case 2 prisms are used together
Firstly sunlight light is made to fall on the prism
This makes white light to form spectrum of 7 colors
This spectrum is made to fall on another prism which was held in inverted position
This leads to emergence of sunlight from second prism
Note: - This method was first used by Isaac Newton
Note: - Any light that gives a spectrum similar to that of sunlight is
often referred to as white light.