All Flashcards
Define linear momentum.
A measure of an object's mass in motion, quantifying how much 'oomph' it has.
What is center-of-mass velocity?
The average velocity of a system of objects, treating the system as a single entity.
Define impulse.
The change in momentum of an object when the object is acted upon by a force for an interval of time. Mathematically, it's the integral of force with respect to time, but more simply, it is the product of the average force and the time interval for which it acts.
What is an isolated system in the context of momentum?
A system where no net external force acts, and thus the total momentum remains constant.
Define the Impulse-Momentum Theorem.
The change in a system's total momentum equals the impulse exerted on it from outside the system:
What happens to momentum when there is zero net external force vs. nonzero net external force?
Zero Net External Force: Total momentum of the system stays constant. Nonzero Net External Force: Momentum is transferred between the system and its surroundings.
What are the differences between elastic and inelastic collisions?
Elastic Collision: Kinetic energy is conserved. Inelastic Collision: Kinetic energy is not conserved.
What is the effect of a net external force acting on a system?
The total momentum of the system changes; momentum is transferred between the system and its surroundings.
What happens when two objects collide in a closed system?
Momentum is transferred between the objects such that the total momentum of the system remains constant.
What is the effect of an impulse on an object?
The object's momentum changes by an amount equal to the impulse:
What is the effect of an explosion within a closed system?
The total momentum of the system remains zero (if it was initially at rest), with the individual components moving in opposite directions to conserve momentum.
What happens if the kinetic energy is conserved during a collision?
The collision is classified as elastic.