Rotational Motion Review 1920

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

A fan blade, initially at rest, rotates with a constant acceleration of 0.025 rad/s². What is the time interval required for it to reach a 4.2 rad displacement after starting from rest   

• 1.8 s
• 2.0 s
• 16 s
• 18 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

A tire of 68cm in diameter travels 9.2km. How many revolutions does it make?

• 43.00 rads

• 567 revs

• 4300 revs

• 68cm

A 2.0-kg ball is moving with a constant speed of 5.0 m/s in a horizontal circle whose diameter is 1.0 m. What is the magnitude of the net force on the ball?

• 50 N
• 20 N
• 0 N
• 100 N

A cave dweller rotates a pebble in a sling with a radius of 0.30 m counterclockwise through an arc length of 0.96 m. What is the angular displacement of the pebble?

• 1.6 rad
• -1.6 rad
• 3.2 rad
• -3.2 rad

A bucket on the circumference of a water wheel travels an arc length of 18 m. If the radius of the wheel is 4.1 m, what is the angular displacement of the bucket?

• 1.0 rad
• 4.4 rad
• 3.7 rad
• 2.3 rad

What is the approximate angular speed of a wheel rotating at a rate of 5.0 rev/s?

• 3.2 rad/s
• 1.6 rad/s
• 16 rad/s
• 31 rad/s

A potter’s wheel moves from rest to an angular speed of 0.54 rad/s in 30.0 s. What is the angular acceleration of the wheel?

• 16 rad/s2
• 1.3 rad/s2
• 0.018 rad/s2
• 0.042 rad/s2

An automobile tire with a radius of 0.30 m starts at rest and accelerates at an angular speed of 2.0 rad/s2 for 5.0 s. What is the angular displacement of the tire ?

• 12 rad
• 25 rad
• 2.0 rad
• 0.50 rad