Q.
As shown in figure, the liquid, $L_{1},L_{2}\ and\ L_{3}$ have refractive indices 1.55, 1.50 and 1.20 respectively. Therefore, the arrangement corresponds to
A) Biconvex lens
B) Biconcave lens
C) Concave-convex lens
D) Convexo-concave lens
Explanation
(c) As seen from a rarer medium $(L_{2}\ or\ L_{3})$ the interface $L_{1}L_{2}$ is concave and $L_{1}L_{3}$ is convex. The divergence produced by concave surface is much smaller than the convergence due to the convex surface. Hence, the arrangement corresponds to concave-convex lens
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.