Assignment Chapter One

1. a) What is the momentum of a 1.8 kg rock thrown upwards with a velocity of 23 m/s?

(3 marks)

b) What is the velocity of an object with mass 246 kg, if the momentum is

5.41 X 10³kgm/s [E 30^o S]? (3 marks)

2. An object of mass 326 kg is moving with a speed of 38 m/s. It takes 3.7 s to stop the

object. If the force applied is constant, what is the force? (3 marks)

3. A toy car of mass 364 g roles across the floor with a velocity of 1.8 m/s [right]. It runs

into a spring which applies an average force of 1.3 N for 0.95 s. What is the

final velocity of the car? (3 marks)

4. Because it stole a person's money, an impulse of 10.3 Ns is given to a vending

machine when struck by a fist. The fist used has a mass of 0.75 kg, and was in contact

with the machine for 0.013 s. What was the acceleration of the fist when it hit the

machine? (4 marks)

5. Given the following force time graph, what is the impulse present? (3 marks)

6. A rail car of mass 7.3 X 10³ kg is rolling right at 3.8 m/s when it collides with a rail car of

mass 6.8 X 10³ kg rolling left at 4.1 m/s. They lock together. What is their velocity after

collision? (3 marks)

7. A child of mass 33 kg jumps off of a wagon. After jumping, the child's velocity is

4.0 m/s [right]. If the mass of the wagon is 7.2 kg, determine the velocity of the wagon

after the child jumps off. (2 marks)

8. A space person is motionless a distance of 500.0 m from the safety of the space craft.

The person has exactly 11.32 minutes of air left, and the person's mass is 103.2 kg

including the equipment. The person throws a phaser (for all you Trekkers) at a velocity

of 50.2 km/h away from the space craft in order to get back. If the mass of the phaser is

5.3 kg, how many minutes

of extra air does the person have? (3 marks)

9. A ball of mass 2.8 kg is rolling at 3.5 m/s [E], when it strikes a 3.2 kg ball rolling at

2.7 m/s [W]. After collision, the 3.2 kg ball has a velocity of 1.9 m/s [W 30^o N]. What is

the 2.8 kg ball's velocity after collision? (4 marks)

10. A fire cracker is thrown with velocity 12.0 m/s [W]. While moving in this direction, it

explodes into two pieces. One piece has a mass of 2.1 g and moves with velocity 10.0

m/s [W 70^o S]. What is the velocity of the other piece which has a mass of 1.1 g?

(5 marks)

December 18, 2013