Here's why:
* First Law of Thermodynamics: ΔU = Q + W
* ΔU: Change in internal energy of the system
* Q: Heat added to the system
* W: Work done by the system
* Work Done by Expanding Gas: When a gas expands against a constant pressure, it does work on the surroundings. The work done (W) is calculated as:
* W = -PΔV
* P: Constant pressure
* ΔV: Change in volume
Important Notes:
* The work done is negative because the system (gas) is doing work on the surroundings.
* The first law of thermodynamics states that the change in internal energy is equal to the heat added minus the work done by the system.
* If the gas is compressed (volume decreases), then the work done is positive, as the surroundings are doing work on the system.
Let me know if you'd like more clarification on any aspect of the first law of thermodynamics!
