The variables in the movement of the piston are temperature and volume. Thus, option B is correct.
The gas has been assumed to be the ideal gas. The ideal gas equation has been given as:
[tex]PV=nRT[/tex]
Where, the pressure of the gas has been P
The volume of the gas has been V
The moles of gas have been n
The Boltzmann constant has been R
The temperature of the gas has been T
The piston has been moved upward with the increase in the temperature of the system. The moles of the gas has been the constant value for the system, along with R.
The rise in the temperature has been resulted in the movement of the piston. Thus, the volume of the system has been increased.
Therefore, the variables in the movement of the piston are temperature and volume. Thus, option B is correct.
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