Rotational Motion

Rotational Motion

Inquiry Lab

Angular position

• angle that an object makes with a reference line

• here we use radians

•  $1\ rad=\ \frac{360}{2\pi}=57.3$  

• arc length (rotational displacement)  $s=r\theta$  

Multiple Choice

What is 2 radians in degrees?

• 57.3

• 114.6

• 26.65

angular displacement

•  $\Delta\theta=\theta_{f_{ }}-\theta_i$  

• these are in radians

Multiple Choice

What is the angular displacement in radians if a paint spot on a tire turns from 57.3 degrees to 282 degrees

• 339.3

• 5.9

• 3.9

• 4.9

average angular velocity

•  $\omega_{av}=\frac{\Delta\theta}{\Delta t}$  

Multiple Choice

What is the average angular velocity in radians if a paint spot on a tire turns from 57.3 degrees to 282 degrees in .5 sec

• 339.3

• 7.8

• 1.95

• 4.9