In downhill speed skiing a skier is retarded by both the air drag force on the body and the kinetic frictional force on the skis. Assume the slope angle is θ = 39.5 degree, the snow is dry snow with a coefficient of kinetic friction μk = 0.0400, the mass of the skier and equipment is m = 78.0 kilogram, the cross-sectional area of the (tucked) skier is A = 1.30 m2, the drag coefficient is C = 0.150, and the air density is 1.20 kg/m3.
(a) Find what is the terminal speed?
m/s
(b) If a skier can vary C by a slight amount dC by adjusting, say, the hand positions, find the corresponding variation in the terminal speed? (dvt/dC)
m/s