1. An object of mass 5.3 kg accelerates at a rate of 3.0 m/s2 for a time of 2.7 s. If the object
starts from rest, what is the work done on the object? (3 marks)
2. A force of 230.2 N is applied to the upper corner of a box which sits on a wagon. The force
is applied at an angle of 36.0o to horizontal. If the wagon moves 28.3 m while the force is
applied, how much work was done? (2 marks)
3. A rail car of mass 1.8 X 103 kg is moving with speed 8.3 m/s. How much work must be done
to accelerate it to 27 m/s? (3 marks)
4. The momentum of a car is 3.53 X 104 kgm/s. If the mass of the car is 1.50 X 103 kg, what is
the car's kinetic energy? (3 marks)
5. A truck is loaded with gravel which causes the springs to be depressed a distance of 23.2 cm.
If the mass of the gravel is 800.0 kg, what is the force constant for the truck's springs?
(2 marks)
6. A paper wad is placed on an elastic which is stretched 14.3 cm. The paper wad has a mass
of 8.36 g. The force constant for the elastic is 94.3 N/m. After it is released, what is the speed
of the paper wad, when the elastic is still stretched 4.80 cm? (4 marks)
7. A 946 kg roller coaster starts down from the highest point on its track with an initial velocity of
3.00 m/s. The height of the highest point is 14.6 m above the ground. As the roller coaster
enters a corner, its height above the ground is 4.83 m. How fast will the roller coaster be
traveling at, as it goes into this corner? In order to get marks for this question, you must
answer by using energy concepts. Solutions that do not use energy concepts will receive a
mark of zero. (4 marks)
8. The space shuttle which has a mass of about 2.10 X 105 kg is lifted to a height of 523 km. To
reach this height, it must reach a speed of 2.74 X 104 km/h. How much energy must be given
to the space shuttle in order to achieve this orbit? The mass of the Earth is 5.98 X 1024 kg,
and the Earth's radius is 6.37 X 106 m. (HINT: When on the earth's surface, the shuttle
already has potential energy, which is energy that is not given to it in putting the shuttle into
orbit.) (6 marks)
9. The moon has a mass of 7.34 X 1022 kg and a radius of 1.74 X 106 m. What minimum
velocity must a lunar lander reach in order to come back to earth? (3 marks)
10. What is the change in potential energy of the lunar lander when it is lifted to 2.50 X 102 km
above the moon's surface, if its mass is 7.3 X 103 kg? (4 marks)
11. Object A of mass 3.0 kg is moving towards object B of mass 4.0 kg. A's initial velocity is
+4.1 m/s. Object B's initial velocity is -3.3 m/s, and the collision is elastic. What are the
objects final velocities? (4 marks)
12. Two objects of masses 3.5 kg and 4.5 kg are moving with velocities of +4.4 m/s and
-3.8 m/s respectively. These objects are involved in a head on collision in which 7.0 J of
kinetic energy is lost. What are the objects final velocities? (4 marks)
December 18, 2013