Rotational Motion and Angular Momentum

Question 1

What is the definition of rotational motion?

Answer 1

Rotational motion is the motion of an object around a fixed point or axis.

Question 2

True or False: Angular momentum is conserved in a closed system.

Answer 2

True

Question 3

What is the formula for angular momentum (L)?

Answer 3

L = Iω, where I is the moment of inertia and ω is the angular velocity.

Question 4

Fill in the blank: The moment of inertia depends on the mass distribution relative to the _____ of rotation.

Answer 4

axis

Question 5

What is the unit of angular momentum?

Answer 5

Kilogram meter squared per second (kg·m²/s)

Question 6

Multiple Choice: Which of the following quantities does NOT affect the moment of inertia of an object? A) Mass B) Distance from the axis C) Shape D) Speed

Answer 6

D) Speed

Question 7

What is the relationship between torque (τ) and angular momentum (L)?

Answer 7

τ = dL/dt, meaning torque is the rate of change of angular momentum.

Question 8

True or False: A larger moment of inertia results in a smaller angular acceleration for a given torque.

Answer 8

True

Question 9

What is the principle of conservation of angular momentum?

Answer 9

In the absence of external torques, the total angular momentum of a system remains constant.

Question 10

Fill in the blank: The angular velocity of an object is measured in _____ per second.

Answer 10

radians

Question 11

Multiple Choice: Which of the following is a vector quantity? A) Angular speed B) Torque C) Angular displacement D) All of the above

Answer 11

B) Torque

Question 12

What does it mean for an object to be in rotational equilibrium?

Answer 12

The net torque acting on the object is zero.

Question 13

True or False: Angular displacement is measured in degrees or radians.

Answer 13

True

Question 14

What is the relationship between linear velocity (v) and angular velocity (ω)?

Answer 14

v = rω, where r is the radius.

Question 15

Fill in the blank: The moment of inertia for a solid cylinder about its axis is _____.

Answer 15

1/2 m r²

Question 16

Multiple Choice: Which equation represents the rotational analog of Newton’s second law? A) F = ma B) τ = Iα C) v = rω D) L = Iω

Answer 16

B) τ = Iα

Question 17

What is the effect of increasing the radius on the moment of inertia of a rigid body?

Answer 17

Increasing the radius increases the moment of inertia.

Question 18

True or False: A spinning figure skater can increase their rotation speed by pulling their arms in.

Answer 18

True

Question 19

What is the term for the rotational analog of linear momentum?

Answer 19

Angular momentum

Question 20

Fill in the blank: The _____ of an object is a measure of its resistance to changes in its rotational motion.

Answer 20

moment of inertia

Question 21

Multiple Choice: Which of the following has the highest moment of inertia? A) A thin rod about its end B) A solid sphere C) A thick cylinder D) A hollow cylinder

Answer 21

A) A thin rod about its end

Question 22

What type of motion does a wheel undergoing fixed-axis rotation exhibit?

Answer 22

It rotates around a stationary axis that does not change position.

Question 23

True or False: The angular momentum of a system can change if an external torque is applied.

Answer 23

True

Question 24

What is the relationship between angular acceleration (α) and torque (τ)?

Answer 24

α = τ/I, meaning angular acceleration is proportional to torque and inversely proportional to moment of inertia.

Question 25

Fill in the blank: The _____ of a rigid body is the sum of the products of its mass elements and the square of their distances from the axis of rotation.

Answer 25

moment of inertia