Sadi Carnot, in 1824, proposed that the maximum efficeincy would occur is all the thermal energy, measured in Kelvins, was transfered directly to and from the energy reservoirs into and out of the heat engine during a cycle.
(This means no loss in thermal energy as can occur in the setup above.)

Power is defined as how quickly energy is delivered or received.

The area on a PV diagram that shows a cycle is the work of the gas. In a heat engine this cycle occurs over and over at regular time intervals. The time in the power equation's denominator is the time to complete one heat engine cycle. This is refered to as the period.

The frequency is the measured in Hertz, [Hz.] It is the inverse of the period. Therefore,

This Caterpillar mining dump truck is one of the largest dumptrucks in the world. (Look at the ladder at the front of the truck to get into the driver's seat.) Everytime a cylinder in its engine moves up and down, it completes a themodynamic cycle that can be picutred on a PV-diagram. IF the thermodynamic cycle of the cylinder is shown below, then how much power is generated by each stroke when the engine is running at 2000 rpm's, 33 Hz.

by Tony Wayne ...(If you are a teacher, please feel free to use these resources in your teaching.)