Conservation of momentum

In any collision (crash) the ______ is ALWAYS constant

• total momentum

• total speed

• total velocity

• kinetic energy

A 2-kg object is moving with a momentum of 10 kg.m/s right. What is its velocity?

• 5 m/s right

• 0.2 m/s left

• 20 m/s left

• 20 m/s right

Two objects are moving towards each other as shown in the diagram. The magnitude of p1 and p2 are 20 and 10 kg.m/s, respectively. What is the total momentum of the two objects?

• 30 kg.m/s right

• 10 kg.m/s right

• 10 kg.m/s left

• 30 kg.m/s left

Two objects are moving towards each other as shown in the diagram. The magnitude of p1 and p2 are 20 and 10 kg.m/s, respectively. What is the total momentum of the two objects AFTER COLLISION?

• 30 kg.m/s right

• 10 kg.m/s right

• 10 kg.m/s left

• 30 kg.m/s left

Two objects are moving towards each other as shown in the diagram. The magnitude of p1 and p2 are 20 and 10 kg.m/s, respectively. AFTER COLLISION, m1 moves to the left with magnitude of p1 = 10 kg.m/s, what is p2?

• 20 kg.m/s right

• 10 kg.m/s right

• 10 kg.m/s left

• 20 kg.m/s left

A small box slides across a frictionless surface with a velocity of 2 m/s and a mass of 4 kg. A larger box with a mass of 8 kg that is stationary. Which box have greater momentum?

• the small box

• the large box

• they are equal

In a physics experiment, two carts of mass 1.5 kg each are rolled towards each other.  The orange cart has a velocity of 2 m/s and the blue cart has a velocity of -1m/s.  The carts stick together when they collide.  Calculate their final speed.

• 0.5 m/s
• 1.0 m/s
• 0.33 m/s
• 0.67 m/s

While playing pool, the white cue ball strikes the 8 ball. Before the collision, the cue ball's velocity was 10 m/s and the 8 ball was at rest. If both ball's have a mass of 0.15 kg and the cue ball's velocity after the collision is 2 m/s, what is the 8 ball's velocity?

• 2 m/s
• 8 m/s
• -2 m/s
• 1.5 m/s

A large box slides across a frictionless surface with a velocity of 12 m/s and a mass of 4 kg,  collides with a smaller box with a mass of 2 kg that is stationary.  The boxes stick together. What is the velocity of the two combined masses after collision?

• 0 m/s
• 4 m/s
• 8 m/s
• 12 m/s

If the collision is elastic, then both momentum and kinetic energy of the system are conserved.

• True

• False