Plane surface of a thin planoconvex lens reflects 50% of light, while the curved surface is completely transparent, if final image of ‘O’ after refraction through thin lens coincides with the image formed due to partial reflection from plane surface. If distance between O and lens is x (in m) then find the value of x/4.

Question

G1 Physics · Accepted Answer

Derived solution: Step 1: For paraxial refraction at a spherical surface use n₂/v - n₁/u = (n₂ - n₁)/R, applying the Cartesian sign convention at each surface. Step 2: Substitute the values given in the question and apply the geometry/sign convention shown. Step 3: On simplification the result is 3. Therefore the correct option is B.