The minimum velocity required for an object to escape earths gravitational pull is
\
.
Where
is the velocity of an object,
is the distance from the center of earth,
is gravitational constant and
is the mass of earth.
Find the relation between
and
.

Apply power rule of integration:
.

The minimum velocity required for an object to escape earths gravitational pull is
\
.
The initial velocity is
.
The radius of earth is
.
The initial velocity required for an object to escape earths gravitational pull:
\Substitute
and
in
.

.
Substitute
in
.

.
.