JEE Advanced2019PhysicsRay OpticsActual
Three glass cylinders of equal height H = 30 c m and same refractive index n = 1.5 are placed on a horizontal surface shown in figure. Cylinder I has a flat top, cylinder I I has a convex top and cylinder I I I has a concave top. The radii of curvature of the two curved tops are same R = 3 m . If H 1 , H 2 and H 3 are the apparent depths of a point X on the bottom of the three cylinders, respectively, the correct sta
Options
- AH 3 > H 1
- B0.8 c m < H 2 - H 1 < 0.9 c m
- CH 2 > H 3
- DH 2 > H 1
Correct answer
C. H 2 > H 3
Step-by-step solution
Case- I : Given, H = 30 c m n = 3 2 Apparent depth ⇒ H 1 = H / n ⇒ 30 × 2 3 = 20 c m Case- I I : R = 300 c m n 2 v - n 1 u = n 2 - n 1 R (Refraction through curved surface) 1 - H 2 - 3 - 2 × 30 = 1 - 3 2 - 300 ⇒ H 2 = 600 29 = 20.684 c m Case- I I I : n 2 v - n 1 u = n 2 - n 1 R ; 1 - H 3 - 3 - 2 × 30 = 1 - 3 2 300 ; H 3 = 600 31 = 19.354 c m