Question

An ideal gas that goes through a cyclical process on a PV diagram and returns to the location on the PV diagram where it began. analyze changes in temperature and thermal energy of the gas change during the cycle. Analyze transfers of energy through heat and work during various stages of the cycle.

note: including formulas in the analysis would be helpful.

Answer 1

The above PV diagram is a cyclic process.

From A to B ---isothermal expansion process ( temperature T₁ )

From B to C --- isochoric process ( volume V₂ )

From C to D --isothermal compression ( temperature T₂ )

From D to A -- isochoric process ( volume V₁ )

First law of thermodynamics ( Q-heat, U-internal energy an W-work done)

From A to B : The system does work W₁ , which equals to heat Q added to system. As there is no change in temperature internal energy of the system is zero.

From B to C : Voume is constant (V₂ ) , Work done during this process is zero

Internal energy of the system

From C to D : Work done by the system is

Internal energy do not change,

Heat

From D to A work done as there is no change in volume.

Internal energy

Heat

Net work done

Net internal energy

Net internal energy of system is zero, so the system is a cyclic process., it returns to the location where it began.