AP EAMCET202119 Aug 2021Morning ShiftPhysicsGravitationActual
A particle is kept on the surface of a uniform sphere of mass 1000 kg and radius 1 m . The work done per unit mass against the gravitational force between them is G = 6 . 67 × 10 - 11 N m 2 Kg - 2
Options
- A3.35 × 10 − 10 J   kg − 1
- B− 3.35 × 10 − 10 J   kg − 1
- C6.67 × 10 − 8 J   kg − 1
- D− 3.35 × 10 − 8 J   kg − 1
Correct answer
C. 6.67 × 10 − 8 J   kg − 1
Step-by-step solution
Work done by a conservative force is the change in potential energy, therefore, W = U f - U i Now, the gravitational potential energy per unit mass or gravitational potential of the particle is, V = - G M r So, the initial potential energy, V i = - 6 . 67 × 10 - 11 1000 1 = 6 . 67 × 10 - 8   J   kg - 1 The final potential energy to take the particle far away from the sphere is V f = - G M ∞ = 0 Work done per unit mass of the particle to take it far away from the spare against the gravitati