Calorific value is measured in:

Options

A. kilo joule
B. kilograms
C. kilo joule per kg
D. kilometre

Explanation

**Step-by-Step Solution:**

1. **Understanding Calorific Value**: Calorific value refers to the amount of heat energy released when a specific quantity of fuel is completely burned. It is an important measure in evaluating the efficiency of fuels.

2. **Definition**: The calorific value is defined as the amount of heat produced by the complete combustion of 1 kg of fuel. This means that when we burn 1 kg of a particular fuel, the total heat energy released during this process is what we refer to as its calorific value.

3. **Units of Measurement**: The calorific value is typically measured in terms of energy per unit mass. The standard unit used for this measurement is kilojoules per kilogram (kJ/kg). This indicates how many kilojoules of energy are produced per kilogram of fuel burned.

4. **Conclusion**: Therefore, the calorific value is measured in kilojoules per kilogram (kJ/kg).

**Final Answer**: The calorific value is measured in kilojoules per kilogram (kJ/kg).

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