### You are 60 kg and run at 3 m/s into a wall.

The wall stops you in 0.05 s. What is the force?

The wall is then padded and stops you in 0.2 s. What is the force?

### A ball is hit with a 300 N force. High speed cameras show the contact lasted for 0.02 s. What was the impulse?

Momentum :

p = mv

Directions: show ALL wo

rk on a separate sheet of paper. Answers are in italicized parenthesis so you can check

your work.

1)

What is the

momentum

of a 2 kg ball that is traveling at 2 m/s?

(4 kgm/s)

2)

What is the

momentum

of a 2

.5

kg ball t

hat is traveling at 5 m/s?

(12.5 kgm/s)

3)

What is the

p

of a 10 kg ball that is traveling at 5 m/s?

(50 kgm/s)

4)

What is the

p

of a 1

.

4 kg ball that is traveling at 6

m/s?

(8.4 kgm/s)

5)

How fast must a 3 kg object be moving to have a momentum of 15 kgm/s?

(5 m/

s)

6)

What is the velocity of

a 9 kg

with

a momentum of

–

13.5 kgm/s?

(

–

1.5 m/s)

7)

What is the mass of an object moving at 5.5 m/s with a momentum of 66 kgm/s?

(12 kg)

8)

What is the

mass of an object moving at

–

51 m/s with a momentum of

–

744

kgm/s?

(14.59 kg)

9)

A 2

kg ball has a momentum of

25 kgm/s. What is the ball’s speed?

(12.5 m/s)

10)

Your brother’s mass is 40 kg and he is riding on a 1.3 kg skateboard at

8.5 m/s. What is the total p

?

(351.05 kgm/s)

11)

Which would have more inertia, a 3 kg ball traveling at 10 m/s o

f a 6 kg ball traveling at 3 m/s?

12)

How could a 40,000 lb truck have the same momentum as a 4,000 lb car?

13)

How could a 180 lb running back have more momentum than a 320 lb lineman?

14)

A 91 kg running back moving at 7.1 m/s runs into a 142 kg lineman moving at 3.

4 m/s. Who wins

the tackle?

Impulse =

Change in Momentum I=Ft OR I=m

Δv

15)

What is the change in momentum of a 3 kg object accelerating from rest to 12 m/s?

(36 kgm/s)

16)

What is the

impulse

of a 4 kg object accelerating from 10 m/s to 12 m/s?

(8 kgm/s)

17)

What is the change in momentum of a 13 kg object accelerating from 20 m/s

to 12 m/s?

(

–

104 kgm/s)

18)

A hockey player shoots, exerting a force of 1844.3 N for 0.16 s on the puck. What is the impulse?

(295.09 Ns)

19)

A net force of 100 N is applied to a wagon for 5 s, what is the change in momentum of the wagon?

(500 Ns

)

20)

A net force of

242.1 N is applied to a wagon for 0.6 s, what is the change in momentum of the

wagon?

(145.26Ns)

Momentum Relationship:

Ft=mΔv

1)

How much force is exerted on a 3 kg object accel