AP Physics 1 momentum conservation flashcards

What is momentum?

Momentum is the product of an object's mass and velocity: $\displaystyle p = mv$.

Define conservation of momentum.

In an isolated system, total momentum before is equal to total momentum after an interaction.

True or false: Momentum is a scalar quantity.

False, because momentum is a vector quantity, having both magnitude and direction.

Difference between elastic and inelastic collisions.

Elastic collisions conserve both momentum and kinetic energy; inelastic collisions conserve momentum only.

Fill in the blank: In a closed system, _____ momentum is conserved.

total

What is the equation for impulse?

Impulse is defined as $\displaystyle J = riangle p = F riangle t$, where $\displaystyle F$ is force.

Describe a perfectly elastic collision.

Both kinetic energy and momentum are conserved. Example: two billiard balls colliding.

Question: What happens in an inelastic collision?

Momentum is conserved, but kinetic energy is not. Objects may stick together.

True or false: Momentum can be negative.

True, because momentum direction can be negative depending on the chosen coordinate system.

What is the conservation of momentum formula?

For two objects, $\displaystyle m_1v_{1i} + m_2v_{2i} = m_1v_{1f} + m_2v_{2f}$.

Define impulse-momentum theorem.

The impulse experienced by an object equals the change in its momentum: $\displaystyle J = riangle p$.

What is a real-world example of momentum conservation?

A car crash where the total momentum of the cars before the crash equals after.

Question: What factors affect momentum?

Mass and velocity of the object.

True or false: Momentum is conserved in all types of collisions.

True, as long as no external forces act on the system.

Comparison: Momentum vs. kinetic energy.

Momentum ($\displaystyle p = mv$) is a vector; kinetic energy ($\displaystyle KE = \frac{1}{2}mv^2$) is a scalar.

Fill in the blank: A larger mass at a constant speed has _____ momentum.

more

What is the effect of a net external force on momentum?

It can change the momentum of an object, violating conservation.

Describe a perfectly inelastic collision.

Momentum is conserved, but objects stick together, maximizing kinetic energy loss.

True or false: Two objects with the same mass can have different momentum.

True, because momentum depends on velocity.

What happens to momentum in an explosion?

Total momentum before is equal to total momentum after, distributed among fragments.