Momentum
What is required for the conservation of momentum to apply in a system?
One dominant external force acting on the system
No net external forces acting on the system
All objects within the system must have the same mass
System must be accelerating
A small moon orbits a planet; which quantity would remain constant over time assuming no external torques or forces affect them?
The speed of the moon as it travels through space near the planet.
The total angular momentum about their common center-of-mass.
The kinetic energy of the moon as it moves along its orbit.
The potential energy between the moon and planet at any point in orbit.
When two ice skaters, initially at rest, push off one another and move in opposite directions, how does the momentum of the system change?
The total momentum decreases to a negative value.
The total momentum increases but remains non-zero.
The total momentum doubles.
The total momentum remains zero.
An archer shoots an arrow at a pumpkin on a stand. The arrow embeds itself into the pumpkin and both fly off of the stand at the same velocity. Momentum is conserved. What type of collision has occurred?
Perfectly inelastic
Elastic
Explosion
Inelastic
A force applied to an object causes it to accelerate; if the mass of the object is then doubled while applying the same force, how will the acceleration compare to the original acceleration?
The acceleration will be halved.
The acceleration will double.
The acceleration will quadruple.
The acceleration will stay the same.
If a 5 kg cart moving at 2 m/s collides with a stationary 10 kg cart and they stick together, what is the final velocity of the combined carts?
1 m/s
1.33 m/s
0.67 m/s
2 m/s
A moving cart collides with a stationary cart on a track where friction can be neglected; if the collision is perfectly elastic, which quantity is conserved for the system?
Both linear momentum and kinetic energy are conserved.
Neither linear momentum nor kinetic energy are conserved due to internal forces.
Only kinetic energy is conserved; linear momentum is not conserved.
Only linear momentum is conserved; kinetic energy is not conserved.

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What happens to an individual force experienced by each member during two astronauts pushing away from each other in space?
They experience forces of equal magnitude and opposite direction.
Both astronauts feel the same force regardless of whether or not they are pushed back.
The force is distributed evenly amongst the team members.
One astronaut experiences a greater force while pushing harder against the other astronaut.
What is a characteristic of elastic collisions?
kinetic energy is conserved
momentum is not conserved
kinetic energy is not conserved
the objects colliding stick together
What must be true for two different masses orbiting each other due solely to their mutual gravity according to Newton's law?
They exert equal magnitude forces on each other but have different accelerations based on their masses.
They have equal accelerations towards each other regardless of their masses differences.
They exert forces directly proportional to their distances from each other at any point in time.
They exert greater forces toward larger masses than smaller ones at all times during orbiting motions.