Question

rays from the sun converge at a point 15 cm in front of a concave
mirror Where should an object be placed, so that its image formed
is equal to the size of the object?​

Answer 1

Answer:

Sun is at infinite distance from the surface of the earth. Now light rays from sun rays after reflection from concave mirror will converge at focus.

It is given that sun rays converge at 15 cm. So, focal length of the mirror = f = 15 cm.

In case of a concave mirror, the size of image and object will be same if the object is placed at 2f.

Hence, in this case object must be place at 2f or 2 × 15 = 30 cm.