Unit 2 - Momentum

Question 1

Give the unit for momentum.

Answer 1

Kgm/s

Question 2

Give the 2 factors that affect the momentum of an object.

Answer 2

The mass and the velocity of the object.

Question 3

Define the conservation of momentum.

Answer 3

The total momentum before an event = the total momentum after the event if no external forces are applied.

Question 4

What does it tell you if an object has a negative momentum?

Answer 4

It is travelling in the opposite direction to an object with positive momentum.

Question 5

What is the momentum of a parked car?

Answer 5

Zero - it isn’t moving.

Question 6

A man of 60kg and a rowing boat of 150kg are still on the water. The man jumps out of the boat to reach the bank of the river. He moves forward at 3m/s. Use the conservation of momentum to calculate the velocity of the boat.

Answer 6

Momentum of man = 3 x 60 = 180 kgm/sMomentum of boat is the same in the opposite direction.Velocity of boat = 180/150 = 1.2m/s