Question

Write a short note on dispersion off white light through glass prism

Answer 1

when sunlight white light is made to pass through a prism it is found that the ray of white light spilt into its constituent colour.this is called dispersion.the refractive index of a medium is different for different wavelengths .when ray of white light fall on it, altogether angle of incidence is equal for all colours,the angle of refraction is different

Answer 2

✍️ INTRODUCTION ✍️

✳️ A glass prism is a transparent object having two triangular ends and three rectangular sides. The refraction of light in glass prism is different from a glass slab. This is because in glass prism, the incident ray of light is not parallel to emergent ray of light.

✳️ When a ray of light enters the glass prism it gets deviated two times. First when it enters the glass prism and second when it comes out of the prism. This is because the refracting surfaces of the prism are not parallel to each other. Also, when the ray of light passes through the prism it bends towards its base.

Dispersion of light :

✳️ In 1665, Isaac Newton discovered that white light consists of seven colours. He found that if a beam of white light is passed through glass prism then it will split in to seven colours. These colours are red, orange, yellow, green, blue, indigo and violet (VIBGYOR).

✳️ Spectrum of white light : The band of seven colours formed when a beam of white light is passes through a glass prism is called spectrum of white light.

✳️ Dispersion of light: The phenomenon of splitting of white light into its constituent seven colours while passing through a certain transparent refractory medium is called dispersion of light.

✳️ The dispersion of white light happens because the angle of refraction of lights of different colours is different while passing through the transparent medium. For example, red colour deviates least and is formed at the upper part of the spectrum and violet colour is deviated maximum and is formed at the bottom of the spectrum.