posted by Anonymous .
A sports car of mass 1300 kg (including the driver) crosses the rounded top of a hill (r = 86 m) at 23 m/s. Determine the normal force exerted by the road on the car. Determine the normal force exerted by the car on the 74 kg driver. Determine the car speed at which the normal force on the driver equals zero.
Ac = v^2/r = 23^2/86 = 6.15 m/s^2
Force of gravity down on car = 1300*9.8 = 12740 N
Force of gravity - force up from road = m a = 1300*6.15 = 7995 N
force up from road = 12740 - 7995 = 4745 N
That should get you started. The rest of the problem is the same idea.