To test the performance of its tires, a car travels along a perfectly flat (no banking) cir-
cular track of radius 268 m. The car increases
its speed at uniform rate of
5.29 m/s?
until the tires start to skid.
If the tires start to skid when the car reaches
a speed of 29.4 m/s, what is the coefficient of
static friction between the tires and the road?
The acceleration of gravity is 9.8 m/s.

Consider the growth of a 20-nm-diameter silicon nanowire onto a silicon wafer. the temperature of the wafer surface is maintained at 2400 k. assume the thermal conductivity of the silicon nanowire is 20 wm-1k-1 and all its surfaces including the tip are subjected to convection heat transfer with the coefficient h = 1×105 wm-2k-1 and t∞ = 8000 k. when the nanowire grows to l = 300 nm, what is the temperature of the nanowire tip (t (x =