Answer :
The efficiency of the engine at the given useful energy and input energy is 28%.
The given parameters:
- Input energy of the engine, = 125 J
- Useful energy of the engine, 35 J
The efficiency of the engine is defined as the ratio of the output energy (useful energy) to the input energy and it is calculated as follows;
[tex]efficiency\ = \frac{0ut put \ energy}{1nput \ energy} \times \ 100\%\\\\efficiency\ = \frac{35}{125} \times 100\%\\\\efficiency\ = 28 \ \%[/tex]
Thus, the efficiency of the engine at the given useful energy and input energy is 28%.
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