Answer: 1/sqrt(2) times.
- A Same
- B 1/sqrt(2) times
- C 1/2 times
- D sqrt(2) times
Correct answer: B. 1/sqrt(2) times
Explanation: vo = sqrt(GM/r). At 2R: vo_new = sqrt(GM/2R) = vo_surface/sqrt(2).
g is maximum at Earth's surface; going up, it falls off as 1/r² (inverse-square); going down, it falls off linearly with depth (since only the mass enclosed within radius r contributes), reaching zero at the centre.
Concept context
Universal gravitation, orbital mechanics, gravitational potential, and escape velocity.