Engineering Board Exam Reviewer · Energy and Power · medium
A motor takes 1.2 kW from the supply and delivers 1 hp (746 W) at the shaft. What is its efficiency?
- 37.8%
- 62.2%
- 160.9%
- 74.6%
Answer
B. 62.2%
Solution
= PoutPin=746/1200=0.622, or 62.2%.
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