Question

What is escape velocity?

Answer 1

Escape velocity is defined as the velocity a body must have in order to escape the gravitational attraction of a particular planet or other object.

Let's say, a body is revolving in an orbit of radius $r$ around a planet of mass $M$.

Escape velocity of body $v_e=\sqrt{\frac{2GM}{r}}$

where

$v_e$ = escape velocity

G = universal gravitational constant

M = mass of the body to be escaped from

r = distance from the center of the mass