Rotational Kinematics

A fan spins with a constant angular speed of 500 radians/second. How long will it take to cover an angle of 2π radians (one revolution)?

• 0.013 s
• 0.002 s
• 76.9 s
• 6.28 s

A merry go round starts from rest, and reaches an angular speed of 2 radians/second in 3 seconds. What is its angular acceleration, and through what angle does it sweep in the 3 second time interval? 

• α = 3/2 rad/s²,   θ=27/4 rad
• α = 2/3 rad/s², θ=3 rad
• α = 2/3 rad/s², θ=6 rad
• α = 6 rad/s², θ=27 rad

A flywheel starts from rest, and has an angular acceleration of 4 rad/s². What will be its angular speed when it has made one revolution? 

• 5.01 rad/s
• 50.27 rad/s
• 2.83 rad/s
• 7.09 rad/s

Two bugs ride a turntable which is rotating at a constant rate of 4 rad/s. Bug A is at a radius of 4 cm, while bug B is at a radius of 8 cm. Which of the following is true? 

• Bug A has a greater rotational speed. 
• Bug B has a greater rotational speed. 
• Bug A has a greater speed. 
• Bug B has a greater speed. 

Two bugs ride a turntable which is rotating at a constant rate of 4 rad/s. Bug A is at a radius of 4 cm, while bug B is at a radius of 8 cm. What is the velocity of bug B?  

• 4 cm/s
• 32 cm/s
• 2 cm/s
• 1 cm/s

A Ferris wheel, rotating initially at an angular speed of 0.50 rad/s, accelerates over a 7.0-s interval at a rate of 0.040 rad/s². What is its angular speed after this 7-s interval?

• 0.2 rad/s
• 0.3 rad/s
• 0.46 rad/s
• 0.78 rad/s

A gear spins at a rate of 400 revolutions/minute. Which choice is closest to its angular speed in radians/second?

• 6.67 rad/s

• 2500 rad/s

• 41.9 rad/s

• 20.9 rad/s

Which has greater linear speed, a horse near the outside rail of a merry-go-round or a horse near the inside rail?

• the inside horse
• the outside horse
• Neither

Which has greater angular speed, a horse near the outside rail of a merry-go-round or a horse near the inside rail?

• The inside horse
• The outside horse
• Neither - they both have the same angular speed

A 0.12-m-radius grinding wheel takes 5.5 s to speed up from 2.0 rad/s to 11.0 rad/s. What is the wheel's average angular acceleration?

• 9.6 rad/s/s

• 4.8 rad/s/s

• 3.1 rad/s/s

• 1.6 rad/s/s