MEDIUM
12th West Bengal Board
IMPORTANT
Earn 100

Explain the formation of rainbow.

Important Questions on Dispersion and Scattering of Light

EASY
12th West Bengal Board
IMPORTANT
 What are the different kinds of emission spectra ? 
HARD
12th West Bengal Board
IMPORTANT
The refractive indices for red and violet lights are 1.5155 and 1.5245 respectively. Find the dispersive power of the glass.
MEDIUM
12th West Bengal Board
IMPORTANT

The refractive indices of the material of a lens for violet and red light are 1.56 and 1.54 respectively. If the focal length of the lens for violet light is 40 cm, then calculate (i) focal length for red light and

MEDIUM
12th West Bengal Board
IMPORTANT
The refractive indices of the material of a lens for violet and red light are 1.56 and 1.54 respectively. If the focal length of the lens for violet light is 40 cm, then calculate  (ii) dispersive power of the material.
HARD
12th West Bengal Board
IMPORTANT

A flint glas convex lens of focal length 20 cm is placed in contact with a crown glass lens. The refractive indices for blue are red lights of crown and flint glass are respectively 1.523,1.515 and 1.664,1.644

(i) Find the nature and focal length of crown glass lens which will form and achromatic combination with the flint glass lens.

HARD
12th West Bengal Board
IMPORTANT

A flint glass convex lens of focal length 20 cm is placed in contact with a crown glass lens. The refractive indices for blue are red lights of crown and flint glass are respectively 1.523,1.515 and 1.664,1.644

(ii) What is the focal length of the combination?

MEDIUM
12th West Bengal Board
IMPORTANT
Show that for a single refraction at a plane surface the dispersion is proportional to the tangent of the angle of refraction.
MEDIUM
12th West Bengal Board
IMPORTANT
The mean refractive indices of two specimens of glass are 1.52 and 1.66 respectively. The differences in the refractive indices for the same two lines in the spectrum are 0.13 for the first and 0.22 for the second. Find the focal length of the lens of the second glass which when combined with a convex lens of the focal length of the first will make an achromatic combination.