A 1.0 kg toy car is released at the top of a frictionless track on the left and rolls off of the track from its right side ramp. The car starts at a height of 0.80 m, goes through a 0.50 m diameter loop, and exits the ramp at a
height of 0.25 m.

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.