Calculating Q Transferred in PV Graphs | Thermodynamics

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To calculate Q transferred in a PV graph, one must consider the relationship between internal energy, heat, and work, expressed as U = Q - W. For processes with a slope, work can be determined from the pressure and change in volume. In isochoric processes, where volume remains constant, Q can be found indirectly since no work is done. The method of calculation may vary depending on whether the process is adiabatic or involves specific substances, necessitating the use of the ideal gas equation or relevant tables. Understanding these principles is crucial for accurately determining heat transfer in thermodynamic systems.
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How do i calculate Q transferred in a PV graph (Pressure / Volume)? More specifcally, when it is a slope. All that was given is pressure and volume from the graph.

Also, in an isochoric process, how would one go about finding Q? I spent so much time on thermodynamics yet i still don't know how to find it.
 
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Generally, there is no direct way to do so. You have to consider that

U = Q - W

The internal energy is dependant on temperature. Work is always a function of pressure and change in volume. There are interesting relationships for example if the process is adiabatic, so it depends on the situation. A combination of the ideal gas equation, adiabatic equation or use of saturation/compressed water/refrigerant tables may be needed depending on your problem.
 

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