Q. Figure given below shows a beam of light converging at point $P$. When a concave lens of focal length $16\ cm$ is introduced in the path of the beam at a place $O$ shown by dotted line such that $OP$ becomes the axis of the lens, the beam converges at a distance $x$ from the lens. The value $x$ will be value to
A) $12\ cm$
B) $24\ cm$
C) $36\ cm$
D) $48\ cm$
Explanation
(d) By using lens formula
$\frac{1}{- 16} = \frac{1}{v} - \frac{1}{( - 12)} \Rightarrow \frac{1}{v} = \frac{1}{12} - \frac{1}{16} = \frac{4 - 3}{48} \Rightarrow v = 48\ cm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.