A 1500 kg automobile is traveling up to 20 degree incline at a speed of 6 m/s. If the driver wishes to stop his car in a distance of 5m,determine the frictional force at pavement which must be supplied by rear wheels.

Answer 1

KE=PE+W(fr)
m•v²/2 = m•g•h +F•s=
=m•g•s•sinα +F•s.
F=m(v²/2s - g•sinα)