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3 years ago

A pulley stems has an efficiency of 65.1%. If you perform 350 J of work, how much useful work does the pulley perform?

Physics

1 answer:

maria [59]3 years ago

3 0

<h3><u>Answer;</u></h3>

C. 228 Joules

<h3><u>Explanation;</u></h3>

<em><u>Efficiency of a machine is the energy or work output, divided by the energy or work input, and expressed as a percentage. </u></em> An ideal machine would have an efficiency of 100%.

Efficiency = (work output/work input) × 100%

work input = 350 joules, efficiency = 65.1%

Work output = 350 j × 65.1/100

= 227.85

<u>≈ 228 Joules</u>

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3 years ago

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