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Question
State two factors on which power spent by a source depends. Explain your answer with examples.
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Solution
A source's use of power depends on two things:
- The amount of work done by the source, and
- The time taken by the source to do the said work.
Example: Should a coolie A take one minute to raise a load to a bus roof, and another coolie B take two minutes to do the same, Both coolies accomplish the same amount of work; however, because coolie A works more quickly, the power expended by him is double that of coolie B.
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