Question

A racing car accelerates from 50 km per hour to 200 km per hour in 3.0 seconds along a straight track, and the acceleration is constant during this period. If the axles are 40 cm above the road, what is the magnitude of the angular acceleration of the wheels?

Answer 1

well, in each rotation of the wheel, the wagon goes 2PI*r
speed car=2PIr/timeforonerotation=w*r
w=speedcar/r so change those speed in km/hr to m/s, find wi and wf

angacceleration= (wf-wi)/3sec

Answer 2

So 200km/h is 55.5 m/s and 50km/h is 13.75 m/s.

Wi=55.5/0.4=138.75
Wf=13.75/0.4=34.36

(138.75-34.36)/3= 34.7

Thanks bob. I think this is correct, forgive my lack of units.