Q. In an optics experiments, with the position of the object fixed, a student varies the position of a convex lens and for each position, the screen is adjusted to get a clear image of the object. A graph between the object distance $u$ and the image distance $v,$ from the lens, is plotted using the same scale for the two axes. A straight line passing through the origin and making an angle of $45{^\circ}$ with the $x$-axis meets the experimental curve at $P.$ The coordinates of $P$will be
A) $(2f,\ 2f)$
B) $\left( \frac{f}{2},\frac{f}{2} \right)$
C) $(f,\ f)$
D) $(4f,\ 4f)$
Explanation
(a) It is possible when object kept at center of curvature.
[image:9_image109.emf]
$u = v$
$u = 2f,\ v = 2f.$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.