Question 8Motor Plants - Assistant Engineer

70% to pass

If the piston stroke in a four-stroke cycle diesel engine is 10 1/2 inches and the speed of rotation of the crankshaft is 720 RPM, what is the average piston speed?

A1200 feet/minute
B1260 feet/minute
C1320 feet/minute
D1380 feet/minute
AI Explanation

The correct answer is B) 1260 feet/minute. To calculate the average piston speed, we need to use the formula: Piston Speed (feet/minute) = (Stroke (inches) x RPM) / 12. In this case, the piston stroke is 10 1/2 inches, and the crankshaft speed is 720 RPM. Plugging these values into the formula, we get: Piston Speed = (10.5 inches x 720 RPM) / 12 = 1260 feet/minute. The other options are incorrect because they do not correctly apply the formula to the given information. Option A (1200 feet/minute) is too low, while options C (1320 feet/minute) and D (1380 feet/minute) are too high.

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