Why is the efficiency in the below question 0.25 not 0.33?

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1 Answer
Andrew I.
Jun 5, 2018

See below.

Explanation:

The total amount of energy released by the heat engine per cycle is sum of the used amount and the wasted amount:

#300J+900J=1200J#

Now, given that only #300J# of the total #1200J# is actually used to do work (and the rest wasted) then the efficiency will be:

#300/1200=1/4=0.25#

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