[SOLVED] Conservation of Mechanical Energy 1. The problem statement, all variables and given/known data A ride at a generic amusement park starts off by swinging like a simple pendulum until its amplitude becomes so great that it swings completely around. If the diameter of the circle is 30.0 m, what speed must the ship have at very bottom to just make it to the highest point and sit there with no residual speed. So far, all I know is that the diameter of the circle is 30 m. 2. Relevant equations I don't know how to use the fancy Latex thing to produce my equations, but I'll try my best without it. Mi = Mf (Mechanical Energy, initial and final) Mi = Ug + Ki (Mf would be equal to Ug + Kf) Ug = m * g * h (Potential gravitational energy) Ki = m*Vi^2 / 2 (Kf would be equal to m*Vf^2 / 2) These are what I think, or rather have been using to solve the other problems associated with this problem in this particular section (Conservation of Mechanical Energy) 3. The attempt at a solution I really don't know where to start, the lack of givens is confusing me. Perhaps, if I had the mass of the ship, then I could figure out the potential gravitational energy, and then find then kinetic energy equivalent, and then find the speed from there by rearranging the last equation I gave in part two. Any help with this would be greatly appreciated. This is the last problem in the section, and seems to be the most challenging, as I had no problems with the preceding problems.