Physics
Grade-9
Easy
Question
30 Joules of energy enter a light bulb. 20 joules of energy are transformed into light, how much energy is dissipated as heat?
- 6.7 joules
- 10 joules
- 13 joules
- 100 joules
Hint:
- energy input = useful energy output + waste energy
The correct answer is: 10 joules
- energy input = useful energy output + waste energy
- Waste or heat energy=Input-Output=30-20=10J
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