Angular Motion and Inertia Problems

A flywheel starts from rest and accelerates with a constant angular acceleration of alpha = 3.0 rad/s for 4.0 seconds. What is its final angular velocity. (Source: physicsclassroom.com, )

• 12.0 rad/s.

• 7 rad/s

• 2 rad/s

• 18 rad/s

You have two spheres, both with the same mass (M) and same radius (R). Sphere A is a solid sphere and Sphere B is a hollow shell. Which of the following is true?

Source: Adapted from Pearson Education, Physics 1301 Lecture Outline, Chapter 11

• Sphere A has the larger moment of inertia.

• Sphere B has the larger moment of inertia.

• They have the same moment of inertia.

• It's impossible to know without the mass.

A bicycle tire has a radius of 0.33 m. If the bicycle is moving forward (without slipping) at a linear speed of v = 6.0m/s, what is the angular velocity of the tire? (Source: physicsclassroom.com, )

• 15 rad/s

• 27 rad/s

• 18.18 rad/s

• 19.19 rad/s

A solid disk and a hoop are released from rest at the top of a ramp. They have the same mass and radius. Which one reaches the bottom first? (Source: Adapted from Pearson Education, Physics 1301 Lecture Outline, Chapter 11)

• The hoop

• The solid disk

• They tie

• It depends on their mass.

You are using a 0.40 m long wrench to loosen a nut. You apply a force of 50 N. What is the maximum possible torque you can apply? Source: physicsclassroom.com

• 13.3 N*m

• 45 N*m

• 9 N*m

• 20.0 N*m

To be most effective at opening a heavy, hinged door, where should you push?

Source: Adapted from Pearson Education, Physics 1301 Lecture Outline, Chapter 11

• Near the hinges, perpendicular to the door

• Far from the hinges, parallel to the door .

• • Far from the hinges, perpendicular to the door

• Near the hinges, parallel to the door.

What is the rotational kinetic energy of a 2.0 kg solid sphere with a radius of 0.10 m, rotating at w= 20 rad/s ? (Source: physicsclassroom.com, )

• 1.6 J

• 13 J

• 16 J

• 5.5 J

A force is applied to a dumbbell for a short time t. In Case a, the force is applied to the center of mass. In Case b, the force is applied to one of the ends. In which case does the dumbbell acquire the greater center-of-mass speed?

Source: Adapted from Pearson Education, Physics 1301 Lecture Outline, Chapter 10

• A

• B

• The same

• depends on the dumbbells mass

A solid disk with a mass of 4.0 kg and radius of 0.25 m is free to rotate. A net torque of t = 10.0 N*m is applied to it. What is the disk's angular acceleration Source: physicsclassroom.com

• 40 rad/s^2

• 80 rad/s^2

• 18 rad/s^2

• 25 rad/s^2

You have a spinning solid disk. What happens to its moment of inertia if you keep its mass the same, but double its radius?

Source: Adapted from Pearson Education, Physics 1301 Lecture Outline, Chapter 11

• It stays the same.

• It is double

• it is quadrupled

• it is halved