TRAVEL

How fast must the car travel so that it exerts no force on the road at the crest?

A 915 kg car goes over a hill, with a radius of 43m.

I don’t understand how a car would be able to exert no force on the road. Does the normal force have to be equal to the weight?

Hello,

the forces acting on the car at the crest are: (mg) downward , (N) upward and (mv^2/R) upward.

to exert no force on the road the normal force have to be equal to zero.

mg = N + mv^2/R

mg = 0+ mv^2/R

v = sqrt(Rg) = sqrt(43*9.8) = 20.528m/s

car travel

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