posted by Gina .
A 850-kg race car can drive around an unbanked turn at a maximum speed of 61 m/s without slipping. The turn has a radius of 160 m. Air flowing over the car's wing exerts a downward-pointing force (called the downforce) of 11000 N on the car. (a) What is the coefficient of static friction between the track and the car's tires? (b) What would be the maximum speed if no downforce acted on the car?