Problem Practice

A tricycle wheel of radius 0.11 m is at rest and is then accelerated at a rate of 2.3 rad/s² for a period of 8.6 s.  What is the wheel’s final angular velocity?

• 10 rad/s

• 15 rad/s

• 20 rad/s

• 25 rad/s

A potter’s wheel is rotating with an angular velocity of ω = 3.2 rad/s.  The potter applies a constant force, accelerating the wheel at 0.21 rad/s².  What is the wheel’s angular velocity after 6.4 s?

• 4.0 rad/s

• 4.5 rad/s

• 7.1 rad/s

• 5.9 rad/s

A bicycle wheel with a radius of 0.38 m accelerates at a constant rate of 4.8 rad/s² for 9.2 s from rest.  How many revolutions did it make during that time?

• 16

• 32

• 18

• 24

A record is rotating at 33 revolutions per minute.  It accelerates uniformly to 78 revolutions per minute with an angular acceleration of 2.0 rad/s².  Through what angular displacement does the record move during this period?

• 14 rad

• 22 rad

• 12 rad

• 7 rad

A solid cylinder and a hollow cylinder of equal mass and radius are at rest at the top of an inclined plane.  They are released simultaneously, and roll down the plane without slipping.  Which object reaches the bottom of the incline first?

• They reach the bottom at the same time

• Neither reaches the bottom

• Hollow Cylinder

• Solid Cylinder

A tricycle wheel of radius 0.11 m is at rest and is then accelerated at a rate of 2.3 rad/s² for a period of 8.6 s.  What is the wheel’s final linear velocity?

• 2.2 m/s

• 3.1 m/s

• 1.5 m/s

• 0.8 m/s

An ice skater is spinning very fast with her arms tucked into her side.  She wants to slow her rate of rotation.  Without digging her skates into the ice (whereby the increased friction between her skates and the ice would apply an external torque to her), how can she change her rotation rate?

• She should throw her arms out to the side, increasing her moment of inertia

• She should pull her arms in towards her body, decreasing her moment of inertia

• She should pull her arms in towards her body, increasing her moment of inertia

• She should throw her arms out to the side, decreasing her moment of inertia

A bicycle wheel with a radius of 0.38 m accelerates at a constant rate of 4.8 rad/s² for 9.2 s from rest.  What was its linear displacement during that time?

• 77m

• 144m

• 41m

• 27m

A Frisbee of radius 0.15 m is accelerating at a constant rate from 7.1 revolutions per second to 9.3 revolutions per second in 6.0 s.  What is its angular acceleration?

• 6.3 rad/s^2

• 1.1 rad/s^2

• 2.3 rad/s^2

• 0.9 rad/s^2

Which one of the following are unable to succesfully operate aeroplanes?

• Humans

• Pilots

• Mice

• Astronauts