Gravitational Potential energy:
The Gravitational potential energy of
an object at a point above the ground
is defined as the work done in raising
it from the ground to that point against
gravity.
Consider an object of mass "m" is raised
to heighth from the ground.
A force is required to do this. the
minimum force required to raise the
object is equal to the weight of the
object[mg]
The object gains energy equal to the
work done on it. Let the work done on
the object against gravity be "w"
WorkDone=W= Force x displacement
=mgxh
..W=mgh
since the workdone on the object is
equal to "mgh" an energy equal to "mgh"
units is gained by object.This is the
potential energy of object at height "h"
.. P.E=mgh
