During a single rotation of a 4-stroke cycle gasoline engine crankshaft, the engine undergoes?

• A. Power Stroke Followed by Exhaust
• B. Intake Stroke Followed by Exhaust
• C. Compression Stroke Followed by Exhaust
• D. Intake Stroke Followed by Power

Answer: (A)

In a four-stroke engine, each stroke spans 180 degrees of crankshaft rotation, and a full engine cycle takes two crank revolutions. If you start counting from the moment of ignition (the end of the compression stroke), the next two strokes you see in sequence are the power stroke, where combustion drives the piston downward and produces work, followed by the exhaust stroke, where burnt gases are expelled. Both occur within a single 360-degree turn of the crank, so a single rotation includes the power stroke and then the exhaust stroke. The other pairings either aren’t consecutive within one rotation or don’t align with the engine’s four-stroke sequence.