An ideal gas at pressure, volume, and temperature, P0, V0, and T0, respectively, is heated to point A, allowed to expand to point B also at A’s temperature 2T0, and then returned to the original condition. The internal energy decreases by 3P0V0/2 going from point B to point T0. How much heat left or entered the gas from point B to point T0?

Why does the equilibrium position of the spring change when a mass is added to the spring? will the mass oscillate around the new equilibrium position of the spring or the previous position without a mass attached to the spring? if the equilibrium position of the spring changes by 20 cm (assuming no initial mass) when a mass is added to the spring with constant 4.9 kg/s^2, what is the mass of the object attached to the spring?