Work Input vs Work Output in Pulley Systems

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In an ideal pulley system, work input equals work output, but real systems experience friction that disrupts this balance. Friction creates a torque that opposes pulley rotation, leading to a loss in efficiency. To determine the percentage of work input that equals work output, one must calculate the work done by friction using torque and angular displacement. The actual work output can then be found by subtracting the work done by friction from the work input. Understanding these calculations is essential for evaluating the performance of real pulley systems.
moomoocow
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hello again,
i know that in an ideal pulley system, work input is equal to work output..however in reality, that is not possible due to friction

but what confuses me is that within what percentage is work input=work output?
how are we supposed to find the percentage?

thank you!
 
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In a real pulley, the friction results in a torque that opposes the rotation of the pulley. If you know the torque and the angular displacement you can calculate the work done by friction. The work output is the work input minus the work done by friction.
 

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