rotational motion

What is rotational motion?

• motion of a body that spins about an axis

• motion of a body in a straight line

• any collision in which momentum is conserved

• any collision in which kinetic energy is conserved

What is the unit for angular displacement?

• meters

• radians

• radians/second

• radians/second²

What is the unit for arc length?

• meters

• radians

• rad/sec

• rad/sec²

What is the unit for angular speed?

• meters

• radians

• rad/sec

• rad/sec²

What is the unit for angular acceleration?

• meters

• radians

• rad/sec

• rad/sec²

To convert from degrees to radians:

• multiply by $\frac{\pi}{180}$ 

• multiply by  $\frac{180}{\pi}$  

• multiply by  $2\pi$  

• divide by  $2\pi$  

one revolution is equal to

• $\pi$

• $2\pi$

• $\frac{180}{\pi}$

• $\frac{\pi}{180}$

one revolution is equal to

• 45^o

• 90^o

• 180^o

• 360^o

Which of the following variables canNOT be negative?

• angular displacement

• arc length

• radius

• they actually can all be negative

Find the angular acceleration of a spinning amusement park ride that initially travels at 0.50 rad/s then accelerates to 0.60 rad/s during a 0.50 s interval.

• 0.64 rad/s²

• 25 rad/s²

• 0.20 rad/s²

• 3.0 rad/s²