A(b + 25.0) g mass is hung on a spring. as a result, the spring stretches (8.50 a) cm. if the object is then pulled an additional 3.0 cm downward and released, what is the period of the resulting oscillation? give your answer in seconds with 3 significant figures. a = 13 b = 427

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.