In an experiment, 4.5 kg of fuel was completely burnt. The heat produced was measured to be 180,000 kJ. Calculate the calorific value of the fuel.

The amount of heat produced by the complete combustion of 1 kg of fuel is known as the calorific value.

The heat produced by 4.5 kg of fuel = 180000 kJ

The heat produced by 1 kg of fuel = $\begin{array}{ccc}\frac{180000}{4.5}& =& 40000 \mathrm{kJ}/\mathrm{kg}\end{array}$

Hence, the calorific value of the fuel is 40000 kJ/kg