Unit 4: Linear Momentum
Physics 1 · Unit 4 · Paper 1

Linear Momentum unit test

A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.

Paper 1Paper 2Paper 3
Each paper is built from this unit’s 37 terms and is the same for everyone, so a teacher can assign “Unit 4, Paper 1” and every student sits the identical test. Multiple choice is marked objectively; the written sections you mark yourself against the model answer and rubric.
Suggested time 34 min 31 points0/17 attempted
1

Inelastic collision

2

Momentum

3

Reading a force-time graph

4

An explosion is a collision run backward

5

Impulse from a force–time graph

6

Momentum vs kinetic energy

7

Two-dimensional collisions

8

Explosions

9

Recoil

10

Elastic collision

11

Why momentum is conserved in collisions

12

Perfectly inelastic collision

Short answer 1. Define or explain: The condition for momentum conservation

3 pts

Short answer 2. Define or explain: Center-of-mass velocity in a collision

3 pts

Short answer 3. Define or explain: Momentum in a system with external forces

3 pts

Short answer 4. Define or explain: Why collisions can ignore friction

3 pts

Free response

7 pts

Cart A of mass 0.60 kg moves to the right at 3.0 m/s on a frictionless track and collides with cart B of mass 0.40 kg, initially at rest. After the collision the carts move together. (a) Calculate the velocity of the combined carts immediately after the collision. (b) Determine the kinetic energy lost in the collision, and explain where that energy went. (c) A student proposes that if the carts had bounced apart elastically instead, cart A would have exerted a larger force on cart B during the collision, assuming the same contact time. Evaluate this claim quantitatively.

Calculate the velocity of the combined carts immediately after the collision.

Determine the kinetic energy lost in the collision, and explain where that energy went.

A student proposes that if the carts had bounced apart elastically instead, cart A would have exerted a larger force on cart B during the collision, assuming the same contact time. Evaluate this claim quantitatively.