Question 153General Subjects - Assistant Engineer

70% to pass

Suppose a prime mover rotates at a steady speed of 900 rpm at rated full load and rotates at a steady speed of 1000 rpm at no load. Assuming that no adjustments have been made to the governor speed control setting, what is the speed regulation of the prime mover expressed in percent?

A10.0%
B11.1%
C88.9%
D90.0%
AI Explanation

The correct answer is B) 11.1%. The speed regulation of a prime mover is calculated as the percentage difference between the no-load speed and the full-load speed, divided by the full-load speed. In this case, the no-load speed is 1000 rpm and the full-load speed is 900 rpm. The speed regulation can be calculated as (1000 - 900) / 900 * 100 = 11.1%. The other options are incorrect because: A) 10.0% is too low. C) 88.9% is the reciprocal of the correct answer, which is incorrect. D) 90.0% is too high.

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