The coefficient of kinetic friction between the oil-covered road
and the car tires. is 0.51
To solve this question, we would consider one of the equations of motion.
v² = u² + 2as, where
v = final velocity, which is also equal to 0
u = initial velocity, which is 20m/s
s = skid marks, which is 40 meters long
a = acceleration, which is unknown
0² = 20² + 2*a*40
0 = 400 + 80a
80a = -400
a = -400/80
a = -5 m/s
Also, it is known that acceleration a = (mu)g, where mu is the coefficient of kinetic friction and g is the acceleration due to gravity.
-5 = mu * 9.8
mu = -5/9.8
mu = 0.51
learn more about equations of motion here https://brainly.com/question/16878713
