"A ski tow operates on a slope of angle 14.3 of length 350m. The rope moves at a speed of 12.4km/hr and provides power for 49 riders at one time, with an average mass per ride of 73.0kg. Estimate the power required to operate the tow." The eqn I used to sum the forces in the x-direction is: EFx= Fcos(theta) - mgsin(theta) = 0 F = (mgsin(theta))/cos(theta) = 8935.3N 12.4km/h = 3.44m/s d/v=t 350m/3.44m/s = t = 101.74s W = F*s = (8935.3N)(350m) W = 3127356.9 J Power = W/dt = 3127356.9J/101.74s P=3.07*10^4 W However, this is not right. I feel like I need to include the force in the y-direction in my work equation, but then again perpendicular forces do now work. Does anyone have any idea what I may be overlooking here?