Angular Kinematics

A free throw is in the air for 1.3 seconds, and the ball rotates 6 times. What is the angular speed of the ball?

• 4.6 rev/sec

• 1661 deg/s

• 29 rad/s

• None of the above

• All the above

A positive angular velocity indicates a _______ movement

• clockwise

• counterclockwise

• general

• good vibes

• accelerating

Angular velocity goes from -20 radians/sec to -12 radians/sec in 2 seconds. What's the angular acceleration?

• 8 rad/s/s (-)

• 8 rad/s/s (+)

• 4 rad/s/s (-)

• 4 rad/s/s (+)

• brain freeze

A fast pitch softball player's arm goes from 90 degrees to 0 degrees in counterclockwise direction (reference: right horizontal from distal). What was the angular distance?

• 270

• 90

• -270

• -90

• 2 pi

A golfer's arm is 0.9 meters long, and the club is 1.2 meters long. At impact, the arm-club system is straight, and rotating at 360 degrees per second. What is the linear (tangential) velocity of the club head?

• 2.1 m/s

• 756 m/s

• 756 rad/s

• 13 m/s

• 13 rad/s

Starting at 0 degrees, velocity is -45 deg/s. what angular position (think about the Unit Circle...) will occur after 3 seconds?

• 225

• 180

• 135

• 45

• 315

If knee angle is 0 during full extension, what is a reasonable peak angle during stance phase of running

• 45

• 60

• 90

• 15

• 0

A pitcher's arm is rotating at 500 deg/s and comes to a stop in 0.13 seconds. What was the average angular acceleration?

• 3846 deg/s/s (-)

• 3846 deg/s/s (+)

• 500 deg/s/s (-)

• 500 deg/s/s (+)

• blank

If angular velocity is clockwise and angular acceleration is counter-clockwise, the system is _______

• braking

• accelerating

• time travelling

• right hand rule

• All the above

A soccer player impacts the ball with a linear velocity of 17 m/s. Their thigh-leg system is 1.2 meters long. What's the angular speed?

• 14 deg/s

• 14 rad/s

• 20.4 deg/s

• 20.4 rad/s

• :(