Question

A spherical mirror and a thin spherical lens have each a focal length of -12 cm. The mirror and the lens are likely to be:

• A. Both concave
• B. Both convex
• C. The mirror is concave and the lens is convex.
• D. The mirror is convex and the lens is concave.

Answer 1

The correct option is A

Both concave

Focal length of a concave lens and a concave mirror are taken negative as per sign convention followed.