8.1 - Rotational Motion

360 degrees in radians is

• 3.14

The time required for one complete revolution is:

• torque

• frequency

• period

• rotational kinetic energy

What is angular velocity

• the rate of angular displacement of an object

• the resistance of an object to change its current state

• the amount of angular motion of an object

Which of these can be measured in rpm?

• Linear Distance

• Angular Distance

• Linear Speed

• Angular Speed

• Angular velocity measured in radians

• The central angle measured in degrees

• The central angle measured in revolutions

• The central angle measured in radians

Calculate the length of an arc with radius 15 cm and central angle of 30°.

• 450 cm
• 5π/2 cm or ≈ 7.9 cm
• 225 cm
• 5π/4 cm or ≈ 3.9 cm

Determine the central angle if the arc length is 10 cm and the radius is 5 cm.

• 2°
• not possible ... "s" is too small
• ≈ 114.6°
• 360°