Sample interview questions: How do you calculate work done in a thermodynamic process?
Sample answer:
Calculating Work Done in a Thermodynamic Process
- Identify the type of work done:
- Pressure-volume work (mechanical work)
- Shaft work (mechanical work)
- Electrical work
-
Magnetic work
-
Determine the appropriate thermodynamic equation:
- Pressure-volume work: W = ∫PdV
- Shaft work: W = τdθ
- Electrical work: W = ∫Vdq
- Magnetic work: W = ∫MdB
Pressure-Volume Work (Mechanical Work)
For a process involving a change in volume:
- If the process is reversible, the integral of PdV is calculated along the reversible path.
- If the process is irreversible, the integral is calculated along the actual path taken by the system.
Shaft Work (Mechanical Work)
For a process involving a rotating shaft:
- τ is the torque applied to the shaft
- dθ is the infinitesimal angle of rotation
Electrical Work
For a process invo… Read full answer