How many revolutions does each tire make before the car comes to a stop, assuming that the car does not skid and that the tires have radii of 0.12 m? Answer in units of rev.

Question

The driver of a car traveling at 46.4 m/s applies the brakes and undergoes a constant deceleration of 1.12 m/s ^2 . How many revolutions does each tire make before the car comes to a stop, assuming that the car does not skid and that the tires have radii of 0.12 m? Answer in units of rev.

Answer 1

Angular velocity W=V/r

46.4(m/s)/0.129(m)

=386.666 radian/s

Vf=Vi-at 0=Vi-at

Vi=at 46.4=1.12t therefore, 1rev=2pie rad

8009pie rad will give (8009/2)

4004.52rev

t=Vi/a t=46.4/1.12

t=41.42857s

Angular displacement Q= ((Wf-W0*t)/2))

= ((386.666*41.428)/2))

=8009pie rad