A bicycle tire is spinning clockwise at 2.50 rad/s. During a time period Dt 5 1.25 s, the tire is stopped and spun in the oppo - site (counterclockwise) direction, also at 2.50 rad/s. Calculate (a) the change in the tire's angular velocity Dv and (b) the tire's average angular acceleration aav.

a) The change in the tire's angular velocity is 5 rads/sec

b) The tire's average angular acceleration is 4 rad/s²

Explanation:

initial angular speed, ω (initial) = - 2.5 rad/s

final speed, ω (final) = 2.5 rad/s

time = 1.25 s

a) The change in tire's angular speed

ω = ω (final) - ω (initial)

ω = 2.5 - (-2.5) rad/s

ω = 2.5 + 2.5 (rad/s)

ω = 5 rad/s

b) The average angular acceleration

a = ω : t

a = 5 rad/s : 1.25 s

a = 4 rad/s²