Question
The coefficient of kinetic friction between tires and dry pavement is about 0.80. Assume that while travelling at 27m/s you lock your brakes and as a result the only horizontal force on the car is the frictional one.
How many seconds does it take you to bring your car to a stop?
How many seconds does it take you to bring your car to a stop?
Answers
Henry
a = u*g = 0.8 * (-9.8) = -7.84 m/s^2
V = Vo + a*t = 0
27 - 7.84*t = 0
-7.84t = -27
t = 3.44 s.
V = Vo + a*t = 0
27 - 7.84*t = 0
-7.84t = -27
t = 3.44 s.