What input work is required for this machine

AI Thread Summary
To determine the input work required for a machine with 25% efficiency performing 200 J of external work, the calculation confirms that the input work is indeed 800 J. This is derived from the efficiency formula, where efficiency equals output work divided by input work. The discussion confirms that the initial assumption of 800 J as the required input work is correct. The participants express agreement and welcome each other to the forum. The conversation emphasizes understanding machine efficiency in practical applications.
hisbul
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Homework Statement


a 25% efficient machine performs external work of 200 J. what input work is required?..please answer,,is the answer is 800 J?



Homework Equations





The Attempt at a Solution


800 J
 
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welcome to pf!

hi hisbul! welcome to pf! :smile:
hisbul said:
a 25% efficient machine performs external work of 200 J. what input work is required?..please answer,,is the answer is 800 J?

yup! :biggrin:
 

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