Section 8.2
Rotational Dynamics
Practice Test
1.
In Figure 8-3, if the door is 0.90 m wide and you exert a force of 2.0 N as in the picture on the top right, what is the magnitude of the resulting torque on the door?
a.
2.9 N·m
b.
1.8 N·m
c.
0.45 N·m
d.
0.40 N·m
Hint
2.
In Figure 8-3, why does applying a force as in the picture at the bottom left result in no effect?
a.
The force is applied parallel to the lever arm.
b.
The force is applied at the axis of rotation.
c.
The force is applied perpendicular to the axis of rotation.
d.
The force is applied perpendicular to the lever arm.
Hint
3.
The product of the force and the lever arm is called __________.
a.
torque
b.
power
c.
range
d.
equilibrium
Hint
4.
In Figure 8-5, if
m
1
= 1.0 g,
m
2
= 5.0 g, and
r
1
= 6.0 cm, what is
r
2
?
a.
0.83 cm
b.
1.2 cm
c.
1.2 m
d.
0.83 m
Hint
5.
In Figure 8-3, why does applying a force as in the picture at the top left result in no effect?
a.
The force is applied parallel to the lever arm.
b.
The force is applied perpendicular to the lever arm.
c.
The force is applied perpendicular to the axis of rotation.
d.
The force is applied at the axis of rotation.
Hint
