Question

A car whose brakes are locked skids to a stop in 200 ft from an initial velocity of 50 mi/hr. Find the coefficient of sliding friction.

Answer 1

First convert 50 mi/hr to ft/s
Vo= 73.33 ft/s
g = 32.2 ft/s^2

M*Vo^2/2 = M*g*Uk*X
M cancels out
Vo^2 = 2*g*Uk*X = 5378 ft/s^2
Uk = 5378/(2*32.2*200)= 0.4175

Answer 2

thank you!