Free Practice Quiz Question List

10 - Angular Momentum and Rolling Motion Online Quiz Questions

Use this free practice quiz with 20 questions to review 10 - Angular Momentum and Rolling Motion, test your knowledge, and prepare for your next test or exam.

20 questions

True or false

1 point

True or false: In ideal rolling without slipping, static friction can exert a torque on the rolling object without doing net work on it.

A
True
B
False

Choose one

1 point

Under which condition is the total angular momentum of a system conserved about a selected axis?

A
The object has constant angular speed.
B
The net external torque about the selected axis is zero or negligible.
C
The object has no rotational kinetic energy.
D
The object is rolling without slipping.

Written response

1 point

A student on a frictionless rotating platform has an initial angular speed of $3\,\mathrm{rad/s}$ . Pulling in their arms reduces the system’s moment of inertia to one-half its initial value. Assuming negligible external torque, what is the final angular speed? Enter the number in rad/s.

Fill in the blank

1 point

For an object rolling without slipping, the center-of-mass speed satisfies .

Choose one

1 point

A solid cylinder and a thin hoop have the same mass, radius, and angular speed about their central axes. Which object has the smaller rotational kinetic energy?

A
The hoop, because all of its mass is at the axis.
B
The hoop, because its radius is larger in the formula.
C
The solid cylinder, because its moment of inertia is smaller for the same $M$ and $R$ .
D
They have equal rotational kinetic energy because they have equal mass.

Choose all

1 point

A student pulls their arms inward while rotating on a frictionless platform. Which statements are correct? Select all that apply.

A
The total angular momentum of the system remains constant.
B
If the system’s moment of inertia decreases, its angular-speed magnitude increases.
C
The angular momentum of every individual component must remain constant.
D
Internal work can increase the system’s rotational kinetic energy.

True or false

1 point

True or false: A rigid object rolling without slipping generally has both translational and rotational kinetic energy.

A
True
B
False

Written response

1 point

A $2.0\,\mathrm{kg}$ mass hangs from a string wrapped around a pulley with radius $0.50\,\mathrm{m}$ and moment of inertia $1.0\,\mathrm{kg\,m^2}$ . The string does not slip and the axle is frictionless. What is the mass’s downward acceleration? Enter the value in m/s^2 rounded to the nearest 0.01; an absolute tolerance of 0.01 m/s^2 is accepted.

Fill in the blank

1 point

The quantity $\tau_{\mathrm{net}}\Delta t$ , which equals the change in angular momentum for a constant net torque, is called .

Choose one

1 point

A wheel rolls without slipping with center-of-mass speed $4\,\mathrm{m/s}$ . What is the speed of the topmost point of the wheel relative to the ground?

A
0 m/s
B
2 m/s
C
8 m/s
D
16 m/s

Choose all

1 point

A mass unwinds a string from a pulley without slipping. Which equations are valid for analyzing this system? Select all that apply.

A
The hanging mass satisfies $mg-T=ma$ .
B
The pulley satisfies $TR=I\alpha$ .
C
The string constraint during slipping is $a=R\alpha$ .
D
The no-slip string condition is $a=R\alpha$ .

Open ended

1 point

Explain how you would determine whether angular momentum can be conserved for a rotating system whose parts may exert torques on one another.

Choose one

1 point

A solid sphere and a thin hoop of the same mass and radius start from rest at the same height and roll without slipping down identical inclines. Which reaches the bottom with the greater center-of-mass speed?

A
The hoop, because more of its mass is far from the axis.
B
The solid sphere, because it has the smaller ratio $I_{\mathrm{CM}}/(MR^2)$ .
C
They reach the bottom with the same speed because their masses cancel.
D
The hoop, because rotational kinetic energy is absent for a hoop.

Choose one

1 point

A particle is moving in a straight line. About which selected axis is its angular momentum necessarily zero?

A
The particle’s speed is zero
B
The particle’s line of motion passes through the axis
C
The particle is moving perpendicular to the axis
D
The particle’s mass is very large

True or false

1 point

True or false: In ideal rolling without slipping, static friction can exert a torque on the object without converting mechanical energy into thermal energy.

A
True
B
False

Choose one

1 point

A solid disk and a thin hoop have the same mass and radius. The same nonzero net torque is applied about each object’s central axis. Which object has the greater angular acceleration?

A
The hoop, because more of its mass is far from the axis
B
The disk, because its moment of inertia is smaller
C
Both have the same angular acceleration because they have the same mass
D
Neither object accelerates because the torque is the same

Written response

1 point

A particle of mass $2.0\ \mathrm{kg}$ moves at $3.0\ \mathrm{m/s}$ . Its line of motion is $0.50\ \mathrm{m}$ from a selected axis. What is the magnitude of its angular momentum about that axis?

Written response

1 point

A wheel rolls without slipping with center-of-mass speed $3.0\ \mathrm{m/s}$ . What is the speed of the top of the wheel relative to the ground?

Choose one

1 point

A student on a frictionless rotating platform pulls in their arms, reducing the system’s moment of inertia to one-half its initial value. What happens to the magnitude of the angular speed?

A
The final angular speed is one-half the initial angular speed
B
The final angular speed is twice the initial angular speed
C
The final angular speed is unchanged
D
The final angular speed is four times the initial angular speed

Choose one

1 point

A $2.0\ \mathrm{kg}$ mass hangs from a string wrapped around a pulley with radius $1.0\ \mathrm{m}$ and moment of inertia $2.0\ \mathrm{kg\,m^2}$ . The string does not slip, the axle is frictionless, and use $g=10\ \mathrm{m/s^2}$ . What is the mass’s downward acceleration?

A
$2.5\ \mathrm{m/s^2}$
B
$4.0\ \mathrm{m/s^2}$
C
$5.0\ \mathrm{m/s^2}$
D
$10\ \mathrm{m/s^2}$