- angular momentum
- the product of the moment of inertia and angular velocity
- change in momentum
- the difference between the final and initial values of momentum; the mass times the change in velocity
- elastic collision
- collision in which objects separate after impact and kinetic energy is conserved
- impulse
- average net external force multiplied by the time the force acts; equal to the change in momentum
- impulse–momentum theorem
- the impulse, or change in momentum, is the product of the net external force and the time over which the force acts
- inelastic collision
- collision in which objects stick together after impact and kinetic energy is not conserved
- isolated system
- system in which the net external force is zero
- law of conservation of momentum
- when the net external force is zero, the total momentum of the system is conserved or constant
- linear momentum
- the product of a system's mass and velocity
- point masses
- structureless particles that cannot rotate or spin
- recoil
- backward movement of an object caused by the transfer of momentum from another object in a collision