1. The problem statement, all variables and given/known data A small cube (m=0.450 kg) is at a height of 393 cm up a frictionless track which has a loop of radius, R = 58.95 cm at the bottom. The cube starts from rest and slides freely down the ramp and around the loop. Find the speed of the block when it is at the top of the loop. 2. Relevant equations v^2=g (0.66H-2R) 3. The attempt at a solution This was one of those questions that i never understood. The final is coming up and its bothering me that i still don't no how to do this.' The answer's 7.34m/s. obviously the equation i tried above's not right... any help? thanks!