Physics--Chapter 5: Work and Energy
Chapter 5 Test Review
Format: 50 pts (20 content, 30 problem-solving) MC/SA/Problems (some problems in mc, some
open-ended)
Vocab/Know
 work (know definition and when done, when not done)
 energy (know definition, forms of, given situations know what kind of energy is
involved)
o potential
o gravitational potential
o elastic potential
o kinetic
o mechanical
o nonmechanical
*What does friction do to conservation of mechanical energy?
 power (know definition and alternate equations for)
 Other: 1 Nm = 1 J; 1 N = 1
; 1W = 1
Another resource for content: questions at end of chapter, refer to your answer sheet
A few problems to try below (answers given in parentheses, written-out solutions on my
website):
(Other problems to try: solve other unassigned problems from the end of the chapter, refer to
your answer sheet)
1) A 95 kg runner sprints for 30.0 m in 3.4 s. What is the kinetic energy of this runner?
(3700 J)
2) A 3.00 kg toy falls from a height of 10.0 m. Just before hitting the ground, what will be
its kinetic energy? (294 J)
3) What is the kinetic energy of a 0.135 kg baseball thrown at 40.0 m/s? (108 J)
4) A skier with a mass of 88 kg hits a ramp of snow at 16 m/s and becomes airborne. At the
highest point of flight, the skier is 3.7 m above the ground. What is the skier’s
gravitational potential energy at this point? (3.2 × 103 J)
5) A 40.0 N crate is pulled up a 5.0 m inclined plane at a constant velocity. If the plane is
inclined at an angle of 37° to the horizontal and there is a constant force of friction of
10.0 N between the crate and the surface, what is the net gain in potential energy by the
crate? (120 J)
6) A 0.002 kg coin, which has zero potential energy at rest, is dropped into a 10.0 m well.
After the coin comes to stop in the mud, what is its potential energy? (−0.196 J)
7) A pole vaulter clears 6.00 m. With what velocity does the vaulter strike the mat in the
landing area? (10.8 m/s)
8) A bobsled zips down an ice track starting at 150 m vertical distance up the hill.
Disregarding friction, what is the velocity of the bobsled at the bottom of the hill? (54
m/s)
9) A professional skier starts from rest and reaches a speed of 56 m/s on a ski slope 30.0°
above the horizontal. Find the minimum distance along the slope the skier would have to
travel in order to reach this speed. (320 m)
Physics--Chapter 5: Work and Energy
Chapter 5 Test Review
10) A 40.0 N crate starting at rest slides down a rough 6.0 m long ramp inclined at 30.0° with
the horizontal. The force of friction between the crate and ramp is 6.0 N. Find the
velocity of the crate at the bottom of the incline. (6.4 m/s)
11) A 15.0 kg crate, initially at rest, slides down a ramp 2.0 m long an inclined at an angle of
20.0° with the horizontal. Find the velocity of the crate at the bottom of the ramp. (3.7
m/s)
12) A horizontal force of 200 N is applied to a 55.0 kg cart across a 10.0 m level surface,
accelerating it 2.00 m/s2. Find the force of friction that causes the cart to come to rest.
(90.0 N)
13) What is the average power output of a weight lifter who can lift 250 kg 2.0 m in 2.0 s?
(2.5 kW)
14) A jet engine develops 1.0 × 105 N of thrust to move an airplane forward at a speed of 9.0
× 102 km/h. What is the power output of the engine? (250 MW)