# A flat (unbanked) curve on a highway

## A flat (unbanked) curve on a highway has a radius of 220.0 m. A car rounds the curve ata speed of 25.0 m/s.

(a) What is the minimum coefficient of friction that will prevent sliding?

(b) Suppose the highway is icy and the coefficient of friction between the tires and pavement is only one-third what you found in part (a). What should be the maximum speed of the car so it can round the curve safely?

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