Question

Assume the distance between sun and mirror is infinity and the sun is much above the principal axis. Where will the image of the sun be formed?

• A. at f
• B. at R
• C. in focal plane but below principal axis
• D. in focal plane but above principal axis

Answer 1

The correct option is C

in focal plane but below principal axis

Since the sun is at infinity, all the incident rays will be parallel to each other.

A ray passing through the focus will travel parallel to the principal axis after reflection. A ray through C, will retrace its path after reflection.

Therefore, the image will be formed in the focal plane but a point slightly lower than the focus. As the image is formed at a point, a highly diminished image is formed.