Angular Momentum

Multiple Choice

Which of the following equations correctly represents angular momentum for a rotating object?

• L = Iω

• p = mv

• F = ma

• E = mc^2

Open Ended

Why do you think the concept of angular momentum is significant in understanding the motion of objects?

Multiple Choice

Which physical quantity is represented by the symbol L in the equation L = Iω?

• Rotational inertia

• Angular velocity

• Angular momentum

• Linear momentum

Open Ended

Explain how angular momentum is demonstrated in common applications such as diving and figure skating.

Fill in the Blanks

Fill in the blank: According to the conservation of angular momentum, if the net external torque is zero, the final angular momentum is equal to the

angular momentum.

Multiple Choice

What is the angular velocity of the disk immediately after the bullet is embedded, given the mass and speed of the bullet and the disk?

• 0.50 rad/s

• 1.25 rad/s

• 2.00 rad/s

• 0.40 rad/s

Multiple Select

Select all statements that are true about the conservation of angular momentum in the context of a spinning figure skater.

• No significant external torque is applied.

• Rotational kinetic energy increases, not potential energy.

• Angular momentum stays constant.

• Reduced air friction is the main cause of speed-up.

Multiple Choice

Which of the following statements correctly explains why a figure skater's angular speed increases when she pulls in her arms?

• Her angular momentum increases because her moment of inertia increases.

• Her angular speed increases because her angular momentum is the same but her moment of inertia decreases.

• Her angular momentum decreases because her angular speed increases.

• Her moment of inertia stays constant while her angular speed decreases.

Open Ended

Explain why the angular momentum is conserved when a person pulls their arms in while spinning, but the rotational kinetic energy increases.

Multiple Choice

When she pulls in her arms, which of the following statements is correct regarding the change in her rotational kinetic energy and the source of this energy?

• The work she performs on them turns into increased rotational kinetic energy.

• Her angular momentum decreases so as to conserve energy.

• Her moment of inertia is conserved.

• Her rotational kinetic energy is conserved and therefore stays the same.

Multiple Choice

Which of the following quantities is conserved when the student pulls the objects closer while spinning on the stool?

• Angular momentum

• Rotational kinetic energy

• Moment of inertia

• Linear momentum

Fill in the Blanks

Calculate the final angular speed of a student sitting on a rotating stool holding two 1 kg objects when the objects are pulled from 1.1 m to 0.38 m from the axis of rotation. Use the given values for mass, radii, and initial angular speed.

Open Ended

Describe how the change in the moment of inertia affects the angular speed and kinetic energy of the system when the student pulls the masses inward.

Fill in the Blanks

A 100 kg man stands at 2.1 m from the axis of a merry-go-round rotating at 0.25 rev/s. What is the new angular speed when the man walks to the center?

Open Ended

How would you explain the difference between linear momentum and angular momentum in your own words?

Multiple Choice

What is the rotational analog of linear momentum?

• Angular momentum

• Force

• Energy

• Work

Multiple Choice

Which of the following steps is NOT required to calculate the change in rotational kinetic energy for a system?

• Convert angular speed to radians per second

• Calculate the initial kinetic energy

• Calculate the final kinetic energy

• Calculate the mass of the object

Open Ended

What is the change in kinetic energy due to this movement?