Final answer:
An engine overhaul does not reset the total operating time but extends the service life, while a rebuild might reset the operating history. The thermodynamic efficiency is the ratio of work output to heat input. The work performed by an engine in one cycle is the difference between the heat absorbed and heat discarded.
Step-by-step explanation:
When an engine is overhauled, its total time is affected as this refers to the amount of time the engine has been in service since new or since it was last overhauled. An overhaul involves disassembling, cleaning, inspecting, repairing, or replacing necessary parts and then reassembling. It does not reset the engine's total operating time, but rather extends the engine's service life. However, when an engine is rebuilt, it should be brought back to original specifications (as much as possible), and it might be provided with a new serial number. Different regulations may or may not reset the engine's operating history, depending on the certifying agency and the extent of the rebuild.
To assess the thermodynamic efficiency of the engine, we can use the formula:
Concerning the heat absorbed from the high-temperature bath, if the engine discards -1800 J of heat to the low-temperature bath, and assuming a certain efficiency, you can determine how much heat was absorbed initially using the thermodynamic efficiency formula.
The amount of work performed by the engine in one cycle of operation is equivalent to the difference between the heat absorbed from the high-temperature bath and the heat discarded to the low-temperature bath. This work is what propels the engine, thus being a key factor in its performance.