Question

Pue U Power of a lens.
of 50 cm from it. Where is the needle placed in front of the convex lens
if the image is equal to the size of the object? Also, find the power of the
lens.
A convex lens forms a real and inverted image of a needle at a distance​

Answer 1

Answer:

This is a question of physics, I think

Answer 2

(i) In this case needle is the object. Since the image is real, inverted and of same size as the needle, The needle must be at the same distance in front of lens, as the image is behind the lens. Thus, the needle is placed at a distance of 50cm from the lens in the front.

(ii) When the image formed by a convex lens is of the same size as the needle then tha distance of needle from the lens is 2f. *In this case*
2f=50cm
f=50/2 =25cm


Hence power of convex lens is +4.0 diopter