Rotational Motion

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

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

A 0.12-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 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

The relation between linear velocity and angular velocity

• r = v⍵

• ⍵ = vr

• v = r⍵

• a = v⍵

The unit of angular velocity is

• m/s

• m/s²

• rad/s

• rad/s²

Centripetal acceleration is directed

• directed away from the center of the circle

• directed towards the center of the circle

• it is perpendicular to the radius at that point

• It has no direction

The time required for one complete revolution is:

• torque

• frequency

• period

• rotational kinetic energy

For a rotating rigid body, which of the following statements is NOT correct?

• All points along a rotating rigid body move with constant speed
• Points along a rotating body have velocities that continuously change directions
• Points along a rotating body move through the same angle in equal time intervals
• All of the answers are correct