Q. A convex mirror has a focal length $f$. A real object is placed at a distance $f$ in front of it from the pole produces an image at
A) Infinity
B) $f$
C) $f/2$
D) $2f$
Explanation
(c) Here focal length $= f$ and $u = - f$
On putting these values in $\frac{1}{f} = \frac{f}{u} + \frac{1}{v}$
$\Rightarrow \frac{1}{f} = - \frac{1}{f} + \frac{1}{v} \Rightarrow v = \frac{f}{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.