Dispersion by a prism

 

1) When white light passes through a prism, the white light splits into its all seven colour rays components.


2) This phenomenon of splitting of white light is called dispersion.


3) This dispersion happens because different colours of light have different speed in the prism material.


4) So different colour have different refractive index for the prism material.


5) Different refractive index means different angle of refraction, So when there is different angle of refraction, all colours will refracted at different angles and they will come out at different positions of the prism, and this is called Dispersion.


6) It is found that shorter wave length of colour refracted more, So short wave colour bends more, and long wave length colour bends only be very small angle.


7) The order of seven colour from shorter to longer wavelength colours are

Violet (V), Indigo (I), Blue (B), Green (G), Yellow (Y), Orange (O), and Red (R).

 




So violet (V) bends more and Red (R) bends very less.