Angular

A rope swing is 3 meters long and is rotating at 90 deg/s. what's the centripetal acceleration?

• 7.4 m/s/s

• 2700 m/s/s

• 270 m/s/s

• 4.7 m/s/s

• I'm confused

Michael Jordan performs a 360 dunk with an air time of 0.9 seconds. When he lands, it takes him 0.2 seconds to come to a stop. What was his angular acceleration during landing?

• 2000 deg/s/s (-)

• 360 deg/s/s (-)

• 400 deg/s/s (-)

• 80 deg/s/s (-)

• 72 deg/s/s (-)

A quarterback's arm is 0.8 meters long and rotating at 4 rad/s at release. How fast is the ball moving?

• 5 m/s

• 3.2 m/s

• 20 m/s

• 183 m/s

• None of the above

If I wanted to throw a baseball 44.7 m/s (100mph) with an arm that is 0.7 m long, how fast would I have to rotate?

• 64 deg/s

• 64 m/s

• 64 rad/s

• 31 deg/s

• 31 rad/s

If tangential acceleration is -6 m/s/s and the radius of the object is 2.5, what's the angular acceleration?

• 6 deg/s/s (-)

• 4 deg/s/s (-)

• 2.4 rad/s/s (-)

• 2.4 deg/s/s (-)

• 2.5 rad/s/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

The angular velocity is represented by the Greek letter ____.

• ω

• θ

• α

• σ

The angular acceleration is represented by the Greek letter ____.

• ω

• θ

• α

• σ

The relationship between angular acceleration and linear acceleration is _________

• α = a/r

• a = α/r

• α =ar

• a = αr

A Ferris wheel starts at rest and builds up to a final angular speed of 0.70 rad/s while rotating through an angular displacement of 4.9 rad. What is its average angular acceleration?

• 0.01 rad/s/s

• 0.05 rad/s/s

• 1.8 rad/s/s

• 2.6 rad/s/s