Physics
Grade-9
Easy
Question
A cyclist puts 600 J of work on his bicycle and the bicycle gives out 140 J of useful work. Calculate the energy efficiency of the cyclist.
- 42%
- 23.33 %
- 50%
- 100%
Hint:
- Energy input = useful energy output + waste energy
- Efficiency (%) = (useful energy output ÷ energy input) × 100
The correct answer is: 23.33 %
- Energy input = useful energy output + waste energy
- Here useful energy =140 J
- Input Energy =600 J
- Efficiency (%) = (useful energy output ÷ energy input) × 100
- So Efficiency =
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