1. The problem statement, all variables and given/known data From the text: A farm tractor tows a 3700-kg trailer up an 18° incline with a steady speed of 3.2 m/s. What force does the tractor exert on the trailer? (Ignore friction) 2. Relevant equations I'm not sure which are relevant, but here are the ones I have: ƩF=ma ƩFy=mg+FN=may x=.5axt2 3. The attempt at a solution First, I drew the system; one block pulling another with a string between them, up an incline. I calculated the force of gravity (g) on the trailer: mg=3700*9.81 = 36,297N(newtons) . I created tilted coordinates and calculated the y force and x force on the trailer Fy1 = 18cos36,297 = 8.172N Fx1 = 18sin36,297 = -16.038N I figured that a (acceleration) for the ƩFnet must be 0 since the problem says "steady speed". Constant velocity = zero acceleration, right? But this means that net force on the trailer is also zero. I don't understand this. I tried first, F=ma, using 3700, but with a=0, F=0. That doesn't work. Then I tried to break down the components and find each force. I only have the components of the trailer, not the tractor, and I feel like I should have some information about the tractor in order to determine force on the trailer, but I'm not sure where to get this information. That's where I'm stuck. I'm not sure what I'm missing. Any help would be greatly appreciated, since I've been working on this all week and haven't come up with an answer (it is now due tomorrow). Thank you!