Question

A convex lens forms a real and inverted image of a needle at a distance of 50cm 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?​

Answer 1

Explanation:

It is given that the image is formed at a distance of 50cm from the lens.

And since the image is real,

v = +50cm.

This means that,

u = -50cm.

Therefore, the needle must be placed at a distance of 50cm from the lens.

Hope it helps...