All Flashcards
How do you calculate work done by a system at constant pressure?
W = -PΔV, where P is pressure and ΔV is the change in volume.
Describe the steps to determine the change in internal energy of a system using the First Law of Thermodynamics.
- Identify the heat added to the system (Q). 2. Determine the work done on the system (W). 3. Apply the formula ΔU = Q + W.
Compare Isothermal and Adiabatic processes.
Isothermal: Constant temperature, heat transfer allowed. Adiabatic: No heat transfer, temperature can change.
Differentiate between work done by the system and work done on the system.
Work done BY the system: Volume increases (expansion), W is negative. Work done ON the system: Volume decreases (compression), W is positive.
How do you calculate work done by a system?
W = -PΔV, where P is pressure and ΔV is the change in volume. Note the negative sign; work done by the system is negative.
How do you calculate the change in internal energy using the First Law of Thermodynamics?
ΔU = Q + W, where ΔU is the change in internal energy, Q is the heat added to the system, and W is the work done on the system.
How do you determine work done from a PV diagram?
The absolute value of the work done equals the area under the PV curve. Pay attention to the direction: increasing volume (expansion) means negative work (work done by the system), and decreasing volume (compression) means positive work (work done on the system).