The car consumes 6 kg of gasoline per 100 km of track, moving at a speed of 72 km / h

The car consumes 6 kg of gasoline per 100 km of track, moving at a speed of 72 km / h, the engine efficiency is 20%. find engine power

Data: m (mass of gasoline used) = 6 kg; S (distance traveled) = 100 km (in SI S = 100 * 10 ^ 3 m); V (speed of movement) = 72 km / h (in SI V = 20 m / s); η (engine efficiency of a given vehicle) = 20% (0.2).

Reference values: qb (specific heat of combustion of gasoline) = 46 * 10 ^ 6 J / kg.

We express the engine power of a given car from the formula: η = A / Q = N * t / (qb * m) = N * S / (qb * m * V), whence N = η * qb * m * V / S.

Calculation: N = 0.2 * 46 * 10 ^ 6 * 6 * 20 / (100 * 10 ^ 3) = 11,040 W.