Rotational Motion

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

What is the angular speed about the rotational axis of the Earth for a person standing on the surface?

• 7.3 x 10^-5 rad/s
• 3.6 x 10^-5 rad/s
• 6.28 x 10^-5 rad/s
• 3.14 x 10^-5 rad/s

A grindstone spinning at the rate of 8.3 rev/s has what approximate angular speed?

• 3.2 rad/s
• 26 rad/s
• 52 rad/s
• 81 rad/s

 2600 rev/min is equivalent to which of the following?

• 2600 rad/s 
• 43.3 rad/s 
• 273 rad/s
• 60 rad/s

A 0.30m radius automobile tire rotates how many rad after starting from rest and accelerating at a constant 2.0 rad/s² over a 5.0 s interval?

• 25 rad
• 12.5 rad
• 2 rad
• 0.5 rad

A fan blade, initially at rest, rotates with a constant acceleration of 0.025 rad/s². What is its angular speed at the instant it goes through an angular displacement of 4.2 rad?

• 0.025 rad/s
• 0.11 rad/s
• 0.46 rad/s
• 1.2 rad/s

A spool of thread has an average radius of 1.00 cm. If the spool contains 62.8 m of thread, how many turns of thread are on the spool? "Average radius" allows us to not need to treat the layering of threads on lower layers.

• 100
• 1000
• 3140
• 62800

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 Ferris wheel starts at rest and builds up to a final angular speed of 0.70 rad/s while rotating through an angular displacement of 4.9 rad. What is its average angular acceleration?

• 0.01 rad/s/s
• 0.05 rad/s/s
• 1.8 rad/s/s
• 2.6 rad/s/s

The unit of angular velocity is

• m/s

• m/s²

• rad/s

• rad/s²