JEE Main202313 Apr 2023Evening ShiftPhysicsGravitationActual
Two planets A and B of radii R and 1 . 5 R have densities ρ and ρ 2 respectively. The ratio of acceleration due to gravity at the surface of B to A is:
Options
- A2   :   3
- B2   :   1
- C3   :   4
- D4   :   3
Correct answer
C. 3   :   4
Step-by-step solution
The acceleration due to gravity is g = G M R 2 = 4 π G R ρ 3 ⇒ g ∝ ρ · R Thus, the ratio is ⇒ g B g A = 1 . 5 R ρ 2 ρ R = 1 2 × 1 . 5 = 0 . 75 ⇒ g B g A = 3 4