Question

A beam of light is incident on a mirror and after reflection forms a real image. The beam incident on the mirror can be:

• A. parallel if the mirror is concave
• B. converging if the mirror is convex
• C. diverging if the mirror is plane
• D. converging if the mirror is plane

Answer 1

Answer: (A)

parallel if the mirror is concave

Answer 2

A real image is formed when reflected rays actually converge at a point.

1. Parallel beam and concave mirror: A concave mirror is a converging mirror. When a parallel beam of light is incident on it, the reflected rays converge at the focal point (F), forming a real image. This is correct.
2. Converging beam and convex mirror: A convex mirror is a diverging mirror. It always diverges light and forms virtual images. Thus, it cannot form a real image. This is incorrect.
3. Diverging beam and plane mirror: A plane mirror always forms a virtual image behind the mirror. The reflected rays do not converge; they only appear to diverge. Thus, it cannot form a real image. This is incorrect.
4. Converging beam and plane mirror: As explained above, a plane mirror cannot form a real image. This is incorrect.