Notes for Dispersion of light Class Physics Chapter - light Electricity eyes is prepared by our senior and renowned teachers of Param Himalaya
Dispersion of light :
Newton found by his experiment that if a beam of white light is passed through a glass prism , the white light splits to form a band of seven colours on a white screen .
The splitting up of white light into seven colours on passing through a transparent medium like a glass prism is called dispersion of light.
The dispersion of white light occurs because colours of white light travel at different speeds through the glass prism.
When white light consisting of seven colours (Red , Orange , yellow , Green , Blue , Indigo and violet) falls on a glass prism , each colour
In it refracted ( or deviated ) by a different angle , with the result that seven colours are spread out to form a spectrum.
Causes of Dispersion :
- Because each colors’ light has distinct wavelengths, white light disperses into seven colors. Red light has the longest wavelength in this range of seven colors, while violet light has the shortest.
- In a vacuum, all colors of light travel at the same speed. However, in any transparent material, such as glass or water, various colors of light move at different rates.
- Various colors’ lights bend through different angles due to differences in their velocity. Red light travels the fastest through any transparent medium, whereas violet light travels the slowest.
- As a result, red light bends the least while violet light bends the most.
- Thus, the dispersion o tof white light into seven colors happens when various colored photons bend at different angles while passing through a glass prism.