Law of conservation of energy (during a free fall )
Let a object be 'm ' , lay on point 'a ' and is lifted to pt 'h ' and stopped at pt 'b '
therefore work done on the body is mgh.
as the body is at rest at 'b '
Kinetic energy at 'b ' = 0
Potential energy at 'b ' =mgh
Therefore total energy at 'b ' =mgh +0
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