What is escape velocity? Obtain an expression for it.
Escape velocity: -The minimum speed with which a body must be projected
in order that it will escape from the earth gravitational filed is called as
escape velocity.
Expression of it:-consider a body of mass m on the surface of earth
whose mass and radius are respectively represented by M and R.
and earth is F=GMmR2
gravity potential energy
(GPE)=GMmR2
w=F.S=GMmR2
In order to projector body into the space overcoming the earth's
gravitational field it must be give a kinetic energy which is equal to
potential energy.
therefore;
kinetic energy is equal to potential energy.