Q. A glass lens is placed in a medium in which it is found to behave like a glass plate. Refractive index of the medium will be
A) Greater than the refractive index of glass
B) Smaller than the refractive index of glass
C) Equal to refractive index of glass
D) No case will be possible from above
Explanation
(c) $\frac{f_{l}}{f_{a}} = \frac{(\ _{a}\mu_{g} - 1)}{(\ _{l}\mu_{g} - 1)} \Rightarrow f_{l} = \infty$ if$\ _{l}\mu_{g} = 1 \Rightarrow \ _{a}\mu_{l} = \ _{a}\mu_{g}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.