Foundation
Physics Foundation
Sources of Energy
Heating effect of current electric energy and electric power
Question
Which of the following has the least calorific value ?
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Solution
Calorific value is the energy released per unit mass when a fuel burns completely. Among common fuels:
- Diesel: ~45 MJ/kg
- Natural gas: ~50 MJ/kg
- Coal: ~24-30 MJ/kg
- Petrol: ~46 MJ/kg
Coal has the lowest energy density due to high moisture/ash content and less efficient combustion compared to refined fuels like petrol/diesel or clean gas.
Final answer: Coal