A point source of light is placed at a distance, of 2 f from a converging lens of focal length 1 The intensity on the other side of the lens is maximum at a distance

(a) f

(b) between f and 2 f 

(c) 2 f 

(d) more than 2 f.


Share with your friends
Call

The correct answer is (c) 2 f

EXPLANATION: 

The intensity of the light on the other side is maximum where the image of the point source is formed. 

Here u = -2f, f = f, hence from the lens formula 1/v -1/(-2f) = 1/f 

→1/v = 1/f -1/2f = 1/2f →v = 2f 

Hence the image will be formed at 2f distance from the lens on the other side.

Talk Doctor Online in Bissoy App