Un carro de montaña rusa parte del reposo desde una primera cumbre, desciende una distancia vertical de 45 metros y luego sube una segunda cumbre, llegando a la cima con una rapidez de 15m/s. ¿que tan alto está la segunda cumbre? no considere la fricción.

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.