Question

boy can adjust his power of lens 40 d and 60 d. if its far point is at infinity, then his near point will be​

Answer 1

Explanation:

. When the eye is fuly relaxed, its focal length is largest and the power of the eye lens is minimum. This power is 50 D according to the given data. The focal lengts is

As the far point is at infinity, the parallel rays coming from infinity are focussed on the retiN/A in the fuly relaxed condition. HEnce, the distance of the retinN/A from the lens equals the focal length which is 2 cm. <br> b. when the eye is focussed at the near point, the power is maximum which is 60 D. the focal lenth in this case is

1/v-1/u=1/f

1/u=1/v-1/f=1/(2cm)-3/(5cm)

u=-10cm