Find the effective coefficient of kinetic friction between the car and the road.

Question

A 1350-kg car is traveling on a wet road at 22 m/s. The driver suddenly sees a fallen tree on the road and slams on the breaks. The car comes to a stop after skidding a distance of 44.0 m. Find the effective coefficient of kinetic friction between the car and the road.

Answer 1

A 1350-kg car is traveling on a wet road at 22 m/s. The driver suddenly sees a fallen tree on the road and slams on the breaks. The car comes to a stop after skidding a distance of 44.0 m. Find the effective coefficient of kinetic friction between the car and the road.

Kinetic Energy of Car = 1/2 (MV ² )= 1/2 *1350 * 22*22 J = 326700 J

Work Done by friction = KE of Car ( For stopping it)

Work done + force of Friction * Distance move

Force of Friction = 326700 / 44 = 7425 N

Force of Friction = Coefficient of Friction * Wt of Car = Coefficient of friction *Mass of car * 9

Coefficient Of Kinetic Friction = 7425/(1350*9.8) = 0.56