Question

Define the term 'resolving power' of an astronomical telescope. How does it get

affected on

(i) increasing the aperture of the objective lens ?

(ii) increasing the wavelength of the light used ?

Justify your answer in each case.

Answer 1

The resolving power of a telescope is defined as the reciprocal of the smallest angular separation between two distant objects whose images are seen separately..

resolving power = D/1.22× wavelength of light

Here D=diameter or aperture of objective lens

By this formula:-

1)... resolving power is directly proportional to aperture of objective lens so on increasing the diameter /aperture of objective lens the resolving power is also increases.

2) resolving power is inversely proportional to the wavelength of light used .if we increase the wavelength of the light the resolving power of the lens is decreases