In a horizontal closed cylindrical vessel of length L there is a thin piston connected to the right end wall of the cylinder by a spring of rigidity k. The length of the undeformed spring is equal to the length of the vessel. In the space between the left wall of the vessel and the piston, one mole of an ideal monatomic gas is introduced. In this case, the piston is set in such a position that the length of the spring is 1/3 of the length of the vessel. Then the gas is cooled. In this case, the piston is installed in such a new position that the length of the spring is two-thirds the length of the vessel. Find the amount of heat removed from the gas in the cooling process. The heat capacity of the vessel and the piston, friction, as well as the masses of the piston and spring are neglected.

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