Final answer:
The crankshaft of a 4 stroke engine rotates 720 degrees between each ignition event, accounting for the intake, compression, power, and exhaust strokes as represented by the ideal Otto cycle.
Step-by-step explanation:
The crankshaft of a 4 stroke internal combustion engine rotates 720 degrees between each ignition event. In a 4-stroke cycle, there are four stages: intake, compression, power, and exhaust. Each of these stages corresponds to one full rotation of the crankshaft, meaning two rotations, or 720 degrees, are needed to complete all stages and return to the initial position for a single piston.
As part of the process, the ideal Otto cycle is used to represent these stages—although real engine cycles may vary slightly due to factors like friction and variable heat exchange.