1. The problem statement, all variables and given/known data A loaded truck has a mass of 3100 kg. The maximum speed it can maintain on a 5.0° hill is 80 km/h. What constant speed could the truck maintain on a hill with a slope of 10.0°? Assume the total force due to air resistance and friction is 700 N and that it does not vary with speed. 2. Relevant equations ∑F = ma 3. The attempt at a solution I have an exam tomorrow and this is one of the practice questions. The answer is 44.8 km/h, but I have no idea how to get there. What I have worked out so far is the FBD of the truck, and: since a = 0, for θ = 10 ∑F = 0 F - Ffr - mg⋅sin10 = 0 F = Ffr + mg⋅sin10 F = 5975.4 N and vθ=10 = ?? I am having trouble relating this back to a velocity. Also, since there is no variation in air resistance and friction, it would mean that: for θ = 5 F = Ffr + mg⋅sin5 F = 3347.8 N and vθ=5 = 22.2 m/s I feel like I am almost there but I can't quite put the pieces together ... I've though about work and momentum, but those don't seem to fit with the idea of the question ... Does anyone have an idea on where to go from here?? Thanks!