Question

A driver in a car speeding to the right at 24m/s suddenly hits the brakes and goes into a skid, finally coming to rest. The coefficient of static and kinetic friction between the tires and the road are s = .8 and k = 0.7. How far does the car skid?

Answer 1

Answer:

42 m

Explanation:

$v_{o}$ = initial velocity of the car = 24 m/s

$v_{f}$ = final velocity of the car = 0 m/s

μ = coefficient of kinetic friction = 0.7

g = acceleration due to gravity = 9.8 m/s²

a = acceleration due to kinetic frictional force  = - μg = - (0.7)(9.8) = - 6.86 m/s²

d = distance through which the car skids

Using the kinematics equation

$v_{f}^{2} = v_{o}^{2} + 2 a d$

Inserting the values

$0^{2} = 24^{2} + 2 (- 6.86) d$

d = 42 m