Question

A satellite orbits a planet, moving very close to its surface. By what maximum factor can its kinetic energy be increased suddenly, without change in direction, such that it still remains in orbit? 

(a) 1.5 

(b) √2 

(c) 2 

(d) 3

Answer 1

Correct Answer is: (c) 2 

For an orbit close to the planet’s surface, mv²/R = mg.

For escape velocity, v_max² = 2Rg. 

v_max² /v² = 2.