1. The problem statement, all variables and given/known data Hey guys, just wondering if you guys could help me out a bit. A boy on a sled with a total mass of 72kg slides from rest down a hill, which is 35m high. The friction force between sled and snow has a magnitude of 250N. If the slope of the hill makes an angle of 37 degrees with the horizontal, find: a) the gravitational potential energy of the sled at the top of the hill relative to the base. 2. Relevant equations If i am not mistaken the equation for Gav.pot energy is U= GMe * m .........Re2 and the value of g can be found as g = G * Me/ (R + h)2 3. The attempt at a solution I know i have the following from the question: m= 72kg h1=35m Ff= 250N now what i dont get is where the 37 degrees is supposed to come in and i am not quite sure that that is the equation that i am supposed to use. Could someone please explain to me how i would begin this question? I want to solve it my slef but can someone point me in to a direction. thank you. edit: wait a second, i think i was doing it wrong. Would it be like E1g = mgh = (72kg)(9.8m/s2)(35m) = 24696 J ?