Question

Rays of sun converge at 20 cm in front of
concave mirror. Where should object be placed
so that object side is equal to image size.​

Answer 1

Answer:

The ray diagram illustrates that, in case of a concave mirror, the image size becomes equal to the object size when the object distance equals the radius of curvature, i.e, twice the focal length.

So, the object has to be placed at a distance of (15×2)=30 cm in front of the concave mirror.