A student claims that a convex mirror with radius of curvature has a focal length of

PHYSICS · Subjective · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction

Problem

A student claims that a convex mirror with radius of curvature

30\,\text{cm}

has a focal length of

-15\,\text{cm}

. Is the sign and value of the focal length stated by the student correct? Justify your answer briefly.