Stored Mechanical Energy
Energy stored in objects through the application of force eg springs.
Flywheels are used primarily to stored energy, albeit normally for a a very short duration such as the flywheel used in an internal combustion engine.
E = energy stored [J]
I = moment of inertia of the flywheel [kgm2]
ω = angular velocity of the flywheel [rad s-1]
A spring can be used to store mechanical energy.
PE = Potential Energy [J]
k = Spring Stiffness [Nm-1]
x = Spring Displacement [m]