Physics
Grade-9
Easy
Question
A particular chemical process has an energy efficiency of only 3.00%. To complete this large-scale chemical process, 140,000 J of energy is input. What is the useful energy output of this process?
- 4000 J
- 4200 J
- 40000 J
- 420000 J
Hint:
Efficiency (%) = (useful energy output ÷ energy input) × 100
The correct answer is: 4200 J
Efficiency (%) = (useful energy output ÷ energy input) × 100
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