Rotational Kinematics HW 2

What is the average angular acceleration and the angular displacement during the 2 seconds that a rotating object speeds up from 0.5 rads/s to 0.7 rads/s?

• .2 rad/s

• .1 rad/s

• 0 rad/s

• .5 rad/s

A bicycle being repaired is turned upside down, and one wheel is rotated at a rate of 60 rpm. If the wheel slows uniformly to a stop in 15 s, how many revolutions does it make during this time? Hint: first change 60 rpm into rads/s… then label everything you know!)

• 7.5 rev

• 15 rev

• 22.5 rev

• 30 rev

You pedal your bicycle so that its wheel’s rotational speed changes from 5.0 rad/s to 8.0 rad/s in 2.0 s. Determine the wheel’s average rotational acceleration

• 3 rad/s^2

• 5 rad/s^2

• 2.5 rad/s^2

• 1.5 rad/s^2

You pedal your bicycle so that its wheel’s rotational speed changes from 5.0 rad/s to 8.0 rad/s in 2.0 s. Determine the angle through which it turns during the 2.0 s

• 13 rad

• 20 rad

• 17 rad

• 8 rad

A fan is rotating at 500 rpm, then slows to 200 rpm over the course of 30 seconds. What is the fan’s angular acceleration rate? (convert to radians per second squared)

• -1 rad/s^2

• -2 rad/s^2

• -3 rad/s^2

• -4 rad/s^2

A fan is rotating at 500 rpm, then slows to 200 rpm over the course of 30 seconds. Through what angle does the fan rotate during the 30-second slowing interval?

• 2000 rad

• 1540 rad

• 1150 rad

• 1780 rad