In: Physics
How much horsepower would a car need to tow a boat up the Davis Dam Grade Climb?
Pro Tips
Davis Dam assumed grade = 7%
Air density is sea level conditions (.002377 slugs/f^t3)
w(weight) of the boat + trailer + car = 3,922,000 + 150,000 + 4451 Lbs
Crr = coefficient of rolling resistance = .015
Assume Combined CDA is 1555 ft^2
SAE J2807 (Davis Dam Grande Climb) - min speed is 40mpg (59 ft/s)
F(drag) = 1/2p x V^2 x C(d)A
F(rolling resistance) = W x cos x Crr
F(weight) = W x sin
F(sum) = F(drag) + F(rr) + F(weight)
P = F(sum)XV
convert to horsepower = P(1hp/550ft lbf/sec)