Q.
Escape velocity from a planet is Ve . If its mass is increased to 8 times and its radius is increased to 2 times, then the new escape velocity would be:
Velocity of projection of body, at which the body goes out or gravitational field of earth or planet and never return, is called escape velocity. ve=R2GM
where G is gravitational constant, M is mass of plant and Re is radius.
When M=8M,R=2R,
then ve=(2R)2G(8M)ve=2R2GMve=2ve.
Note: Escape velocity is independent of mass of body.