6.1 Impulse and Momentum

The momentum of an object depends upon the object's ___________&_____________.

• size and shape

• mass and speed

• mass and veloctiy

• mass and energy

Answer explanation

It is a vector quantity, so it is velocity, not speed.

Cart A is pulled with a 2 Newton force for 2 seconds, and Cart B is pulled with a 1 Newton force for 3 seconds.  Which cart experiences the greatest impulse?

• Cart B

• Cart A

• they are the same

 The impulse-momentum theorem states that

• the impulse on an object is equal to the change in momentum it causes 

• the force on a moving object is equal to the magnitude of the impulse.

• the impulse on an object is greater than the change in momentum it causes 

• the impulse on an object is less than the change in momentum it causes

 A runner has a momentum of 670 kg m/s and is travelling at a velocity of 9 m/s. What is his mass?

• 6030 kg

• 0.0134 kg

• 74.4 kg

• 80 kg

A boy kicks a football with a force of 20 N, the time the force acts for is 0.3 s.

Calculate the impulse on the ball.

• 1 N·s

• 6 N·s

• 66 N·s

• None of these

Q. The difference between a car hitting a wall vs. a car hitting a hay stack is

• the Impulse on the car hitting the wall is greater

• the change in momentum of the car hitting the wall is greater

• the force on the car hitting the hay stack is greater

• the collision time of the car hitting the hay stack is greater

When the speed of an object is doubled, its momentum...

• remains unchanged in accord with the conservation of momentum.

• doubles.

• quadruples.

• decreases.

Q. If two objects have the same mass, then the faster moving object has ____________ momentum.

• more

• less

• the same

A 5 N force is applied to a 3 kg ball to slow it down from 9 m/s to 3 m/s. What is the impulse on the ball?

• -2.5 N⋅s

• -10 N⋅s

• -18 N⋅s

• -45 N⋅s

 

A boy kicks a football with a force of 20 N, the time the force acts for is 0.3 s. Calculate the impulse on the ball.

• 1 N⋅s

• 6 N⋅s

• 33.3 N⋅s