Question

Select One Correct Option from the following: A transparent thin film of uniform thickness and refractive index $n_{1}$ = 1.4 is coated on the convex spherical surface of radius R at one end of a long solid glass cylinder of refractive index $n_{2}$ = 1.5, as shown in the figure. Rays of light parallel to the axis of the cylinder traversing through the film from air to glass get focused at distance $f_{1}$ from the film, while rays of light traversing from glass to air get focused at distance $n_{2}$ from the film. Then,
(A) $| f_{1} |$ = 3R
(B) $| f_{1} |$ = 2.8R
(C) $| f_{2} |$ = 2R
(D) $| f_{2} |$ = 1.4R.

Answer 1

c option is correct I think

Answer 2

option c and a are correct