The heat engine which has an efficiency of 35% has done a useful work of 700 kJ. determine the mass of kerosene.

To find the mass of kerosene consumed by a heat engine, we will use the equality: Ap / η = Q (heat received) = qk * m, from where we express: m = Ap / (η * qk).

Constants and variables: Ap – perfect useful work (Ap = 700 kJ = 700 * 10 ^ 3 J); η – efficiency of the heat engine (η = 35% = 0.35); qк – specific heat of combustion of kerosene (qк = 4.6 * 10 ^ 7 J / kg).

Calculation: m = Ap / (η * qk) = 700 * 10 ^ 3 / (0.35 * 4.6 * 10 ^ 7) = 43.5 * 10 ^ -3 kg = 43.5 g.

Answer: The heat engine consumed 43.5 g of kerosene.