Question

An automobile traveling at 50.0 km/h has tires of 100.0 cm diameter.
(a) What is the angular speed of the tires about their axles?
1 rad/s

(b) If the car is brought to a stop uniformly in 25.0 complete turns of the tires (without skidding), what is the magnitude of the angular acceleration of the wheels?
2 rad/s2

(c) How far does the car move during the braking?
3 m

Answer 1

I already took this course. It is your turn to try the problems. When we see exactly what you are having trouble with perhaps we can help.

Remember
Torque = rate of change of angular momentum
= I alpha

omega = w = angular speed
angular momentum = I w

alpha = dw/dt = rate of change of w = angular acceleration

tangential speed = v = w r

distance rolled = r theta = 2 pi r*number of turns