Section 11.1
The Many Forms of Energy
Practice Test
1.
You lift a 2.73-kg textbook from the floor to a shelf 1.75 m above the floor. What is the book's gravitational potential energy relative to the floor?
a.
93.1 J
b.
46.8 J
c.
14.3 J
d.
-46.8 J
Hint
2.
A 75-kg rock climber first climbs 25 m to the top of a quarry, then descends 75 m from the top to the bottom of the quarry. If the initial height is the reference level, what is the potential energy at the bottom?
a.
3.7×10
4
J
b.
-5.5×10
4
J
c.
1.8×10
4
J
d.
-3.7×10
4
J
Hint
3.
Objects that are lifted against the force of gravity have stored energy known as __________.
a.
kinetic energy
b.
potential energy
c.
reference levels
d.
resistance
Hint
4.
The equation that represents gravitational potential energy is __________.
a.
PE
g
=
mgh
b.
PE
g
= 1/2
mv
2
c.
PE
g
=
E
+
KE
d.
PE
g
=
Fd
Hint
5.
In Figure 11-5, if the mass of an orange is about 0.6 kg, about how much more gravitational potential energy does the topmost orange have than the one in the juggler's left hand?
a.
60 J
b.
600 J
c.
0.6 J
d.
6 J
Hint
6.
Stored energy that is a result of the gravitational interaction between an object and Earth is __________.
a.
elastic potential energy
b.
mechanical energy
c.
gravitational potential energy
d.
the reference level
Hint
7.
A 75-kg rock climber first climbs 25 m to the top of a quarry, then descends 75 m from the top to the bottom of the quarry. If the initial height is the reference level, what is the potential energy of the system (climber plus Earth) at the top?
a.
1.8×10
4
J
b.
-3.7×10
4
J
c.
3.7×10
4
J
d.
-1.8×10
4
J
Hint
8.
The __________ is the position at which gravitational potential energy is zero.
a.
release point
b.
height
c.
reference level
d.
initial position
Hint
