Free Practice Quiz Question List

9 - Rotational Motion and Dynamics Online Quiz Questions

Use this free practice quiz with 20 questions to review 9 - Rotational Motion and Dynamics, test your knowledge, and prepare for your next test or exam.

20 questions

True or false

1 point

True or false: A nonzero force can produce zero torque about a chosen axis if its line of action passes through that axis.

A
True
B
False

Choose one

1 point

A point on a rotating wheel is $0.50\,\text{m}$ from the axis, and the wheel's angular speed is $4.0\,\text{rad/s}$ . What is the point's tangential speed?

A
0.50 m/s
B
1.0 m/s
C
2.0 m/s
D
8.0 m/s

Choose one

1 point

An object has angular velocity $\omega=-5.0\,\text{rad/s}$ and angular acceleration $\alpha=+2.0\,\text{rad/s}^2$ . What is happening to its rotation?

A
It is rotating counterclockwise and speeding up.
B
It is rotating clockwise and speeding up.
C
It is rotating clockwise and slowing down.
D
It is stationary and beginning to rotate counterclockwise.

Choose one

1 point

Two equal forces are applied at the same distance from an axis. One force makes an angle of $30^\circ$ with the radius, and the other makes an angle of $90^\circ$ . Which force produces the greater torque magnitude?

A
The force at $30^\circ$ , because it acts partly along the radius.
B
The force at $90^\circ$ , because its entire force is perpendicular to the radius.
C
Both forces produce the same torque because their magnitudes are equal.
D
Neither force produces torque because neither force is directed along the axis.

Choose all

1 point

Select all statements that correctly describe different points on a rigid object rotating about a fixed axis.

A
All points on the object have the same angular velocity.
B
All points on the object have the same tangential speed.
C
A point farther from the axis has greater tangential speed when $\omega$ is nonzero.
D
A point closer to the axis always has greater angular velocity.

Choose all

1 point

Select all conditions that are required for an object to be in rotational equilibrium, including any additional condition required for complete mechanical equilibrium.

A
The net torque is zero.
B
The object must be rotating at zero angular velocity.
C
The angular acceleration is zero.
D
For complete mechanical equilibrium, the net force is also zero.

True or false

1 point

True or false: An angular displacement measured in degrees must be converted to radians before it is used in the equation $s=r\theta$ .

A
True
B
False

Written response

1 point

What is the physics term for the perpendicular distance from an axis to a force's line of action?

Fill in the blank

1 point

For a point at radius $r$ on a rotating object with angular velocity $\omega$ , the tangential speed is given by $v_t=$ .

Fill in the blank

1 point

For rotational equilibrium, the net torque must satisfy .

Open ended

1 point

A wheel starts from rest and rotates with constant angular acceleration of $3.0\,\text{rad/s}^2$ for $4.0\,\text{s}$ . Determine its final angular velocity and angular displacement.

Written response

1 point

A wheel rolls without slipping with radius $0.30\,\text{m}$ and angular acceleration $5.0\,\text{rad/s}^2$ . What is the acceleration of its center of mass? Enter the value in $\text{m/s}^2$ .

Choose one

1 point

A solid disk has mass $4.0\,\text{kg}$ and radius $0.50\,\text{m}$ . A net torque of $3.0\,\text{N}\cdot\text{m}$ acts about its center. What is the disk's angular acceleration?

A
1.5 rad/s²
B
6.0 rad/s²
C
12 rad/s²
D
24 rad/s²

Choose one

1 point

A rigid wheel rotates about a fixed axis. How do the angular velocities of two points at different distances from the axis compare?

A
The point farther from the axis has the greater angular velocity.
B
All points on the rigid object have the same angular velocity.
C
The point closer to the axis has the greater angular velocity.
D
Only points on the outer edge have angular velocity.

True or false

1 point

True or false: In the arc-length equation $s=r\theta$ , an angle of $180^\circ$ can be substituted directly for $\theta$ without converting it to radians.

A
True
B
False

Choose one

1 point

A force of $40\,\text{N}$ is applied to a lever at a distance of $0.50\,\text{m}$ from the axis. The angle between the position vector and the force is $30^\circ$ . What is the magnitude of the torque?

A
$10\,\text{N}\cdot\text{m}$
B
$20\,\text{N}\cdot\text{m}$
C
$34.6\,\text{N}\cdot\text{m}$
D
$40\,\text{N}\cdot\text{m}$

Choose one

1 point

A system consists of a $3.0\,\text{kg}$ point mass $0.20\,\text{m}$ from an axis and a $1.0\,\text{kg}$ point mass $0.40\,\text{m}$ from the same axis. What is the system’s rotational inertia?

A
$0.16\,\text{kg}\cdot\text{m}^2$
B
$0.20\,\text{kg}\cdot\text{m}^2$
C
$0.28\,\text{kg}\cdot\text{m}^2$
D
$0.80\,\text{kg}\cdot\text{m}^2$

Choose one

1 point

A rotating object has rotational inertia $2.0\,\text{kg}\cdot\text{m}^2$ . A $9.0\,\text{N}\cdot\text{m}$ counterclockwise torque and a $3.0\,\text{N}\cdot\text{m}$ clockwise torque act on it. What is its angular acceleration?

A
$1.5\,\text{rad/s}^2$
B
$3.0\,\text{rad/s}^2$
C
$4.5\,\text{rad/s}^2$
D
$6.0\,\text{rad/s}^2$

Written response

1 point

A point on a rotating disk is $0.25\,\text{m}$ from the axis, and the disk’s angular velocity is $8.0\,\text{rad/s}$ . What is the point’s tangential speed in metres per second?

Written response

1 point

An object’s angular velocity increases from $4.0\,\text{rad/s}$ to $10.0\,\text{rad/s}$ in $3.0\,\text{s}$ . What is its average angular acceleration?