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Physics

Key Terms

PhysicsKey Terms

Key Terms

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 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
perfectly inelastic collision
collision in which objects stick together after impact and kinetic energy is not conserved
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
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