The kinetic energy needed to project a body of mass m from the surface of earth (radius R) to infinity is
Options
(a) mgR/2
(b) 2mgR
(c) mgR
(d) mgR/4
Correct Answer:
mgR
Explanation:
The kinetic energy =1/2MVe²
The escape velocity Ve=√2gR
Ve²=2gR
= 2mgR/2
=mgR