Question

derive the expression for potential energy

Answer 1

Answer:

As potential energy is the energy possessed by a body by virtue of its height ..
i.e P.E.=mgh

Explanation:

To derive the formula....
Let us consider a body of mass m be taken and kept at a height h by some force F.
Now when the force is removed then the body fall down from height h .
Then work done by body when it is kept at height h is-
Work = force × displacement
W=F×h......(1)
Now when body fall down...
Then acc.to Newton 2nd law 
Force = mass×acceleration
i.e F= m×a....(2)
Now there is acceleration due to gravity then we can use a=g
Then from equation (2)
F = m×g.....(3)
Now put value of force in equation 2
W = m×g×h....(4)
Hence (4)th equation is the required potential energy which stored in body as work done ....

Then P.E.=mgh

Answer 2

Answer:P.E=mgh

Explanation: consider a body of mass m is kept at height h(or displacement =h).

Then,

W=F×S

W=mg×h(mg bcuz mass=m and gravitation force is acting on it)

W=mgh

W=P.E

hope u understand...