1. The problem statement, all variables and given/known data What power is needed to move a 3000lb car up an 8 degree incline with a constant speed of 50mi/h against a frictionless force of 80lb? ans. 68hp 2. Relevant equations [itex]P = Fv[/itex] 1hp = 550 lb-ft/s 3. The attempt at a solution 1st i draw free body diagram summation of force in the horizontal direction Fx = 0 = 3000sin(8) + 80 - Fn Fn = 497.52lb Power = velocity x force = (50mi/h)(1/3600s)(1ft/0.3048m)(1000m/1km)(1km/0.62137mi) = 36,485.56 lb-ft/s = (36,485.56 lb-ft/s)(1hp/(550lb-ft/s)) = 66.34 horsepower where did i get wronged?