6.5.1 Gravitational Potential Energy

It is defined as the work done against the gravitational force to elevate a particle of m to a height h.

If we denote Vg as gravitational P.E.,

Work done=ʃ F dy

mg dy = mg (h₂ – h₁)

= mg  ∆h.

∆vg = mg = ∆h

V_g = mgh

6.5.2 Elastic Potential Energy

If                                                         K = spring constant in N I m

x = distance in m

If the deformation is from x₁ to x₂ then

Potential energy,