How large must the coefficient of static friction be between the tires and the road if the car is to round a level curve of radius 85m at a speed of 95 km/h?

What will be an ideal response?


Answer: We must change the given speed into units of m/s. (95,000 m/hr) (1 hr/ 3600 sec) = 26.39 m/s
The only horizontal force acting on the car is the friction force.
Ff = ?s FN and since the road is level, FN = weight of the car = m g.
Thus, Ff = ?s m g .
For circular motion this friction force is the net or centripetal force on the car .
?s m g = m v2 / R . The m's cancel out.
thus, ?s = v2 /(R g) = (26.39)2 / [(85)(9.8) ] = 0.84

Physics & Space Science

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GIVEN

FIND
The net rate of heat loss to the air (qf)
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Physics & Space Science