What is the distance the plane flew if its engines used up 1440 kg of kerosene while flying

What is the distance the plane flew if its engines used up 1440 kg of kerosene while flying at an average speed of 250 km / h? The useful power of the aircraft engine is 2300 kW, the engine efficiency is 25%

Given: V (average flight speed) = 250 km / h (in SI V = 69.44 m / s); m (mass of used jet fuel) = 1440 kg; Np (useful power) = 2300 kW (2300 * 10 ^ 3 W); η (motor efficiency) = 25% (0.25).

Constants: q (specific heat of combustion of aviation kerosene) ≈ 43 * 106 J / kg (T-1, TS-1, etc.).

The distance that the plane flew can be expressed from the formula: η = Ap / Ns = Np * t / (q * m) = Np * S / (q * m * V) and S = q * m * V * η / Np.

Calculation: S = 43 * 10 ^ 6 * 1440 * 69.44 * 0.25 / (2300 * 10 ^ 3) ≈ 467.4 km.