In changing the state of a gas adiabatically from an equilibrium state \(A\) to another equilibrium state \(B\), an amount of work equal to \(22.3~\mathrm{J}\) is done on the system. If the gas is taken from state \(A\) to \(B\) via a process in which the net heat absorbed by the system is \(9.35~\mathrm{cal}\), the net work done by the system in the latter case is approximately:
(Take \(1~\mathrm{cal}=4.2~\mathrm{J} \))
1. \(15~\mathrm{J}\) 
2. \(20~\mathrm{J}\) 
3. \(14~\mathrm{J}\) 
4. \(17~\mathrm{J}\) 

Two cylinders, A and B, of equal capacity are connected to each other via a stopcock. A contains gas at a standard temperature and pressure. B is completely evacuated. The entire system is thermally insulated. If the stopcock is suddenly opened, then the change in internal energy of the gas is:

An electric heater supplies heat to a system at a rate of \(100~\text{W}\). If the system performs work at a rate of \(75~\text{J/s}\). At what rate is the internal energy increasing?
1. \(20~\text{W}\)
2. \(25~\text{W}\)
3. \(29~\text{W}\)
4. \(27~\text{W}\)