Question

A convex lens and a concave lens having same focal length “f” are combined to form a new lens. What is the power of the combination?​

Answer 1

Answer:

0

Explanation:

The power of the combination becomes zero.

Focal length of Concave lens = -f

Focal length of Convex lens = +f

Their powers respectively will be: 1/-f and 1/+f

Adding both we will get,

1/f + (-1/f) = 0

[which is actually not so useful in real life usage, so most of the combinations will give a non-zero answer as the combined power of lens ;) ]

Happy to help