Physics Chapter 12: Key Terms and Definitions

Energy

The capacity or ability to do work

Kinetic energy

Based on motion

potential energy

Based on position

Conservative force

Has energy conserved from one form to another

nonconservative force

Loss of energy; friction

Dissipative force

Loss of energy to the environment; heat, sound

Law of conservation of mechanical energy

Total mechanical energy for a system is constant

What does the law of conservation of mechanical energy say?

Energy cannot be created or destroyed, only transformed from one form of energy to another form of energy; no exceptions

Momentum

Product of mass x velocity

Law of conservation of momentum

When net force acting on a system is 0, the momentum of the whole is constant

Elastic collision

All kinetic energy is completely transferred from one object to another; no kinetic energy is converted to heat or sound

inelastic collision

Not all kinetic energy is conserved; heat, sound, and friction exist; objects stick to eachother (car wreck)

Impulse

Product of the force that changes the momentum of the object and the time that force was applied to the object