Acar traveling at a steady 20 m/s rounds an 80-m radius horizontal unbanked curve with the tires on the verge of slipping. what is the maximum speed with which this car can round a second unbanked curve of radius 320 m if the coefficient of static friction between the car's tires and the road surface is the same in both cases?

Refer to the diagram shown below.

r = the radius of the curve
m =  the mass of the car
μ = the coefficient of kinetic friction
N = normal reaction

When rounding the curve, the centripetal acceleration is


The inertial force tending to make the car skid is balanced by the frictional force, therefore


When r = 80 m and v = 20 m/s, obtain


When r = 320 m and μ remains the same, obtain


40 m/s

B, if it was a lower watt she could put it in for her normal time and not burn it