Question

the police department determined that the force required to drag a 130 N(29 lb) car tire across the pavement at a constant velocity is called 100N (23 lb ) specifications from the trucks manufacturer claim that the effecrive coefficient of kinetic friction between the tires and road for both new car and truck??

Answer 1

The force of friction is given by:
f = μR, where μ is the friction coefficient and R is the reaction force, which will be equal to the weight.
100 = μ x 130
μ = 0.77