The 3660 W petrol engine has an efficiency of 30%. How long will a glass (200 g) of gasoline last for this engine?

Data: N (gasoline engine power) = 3660 W; η (efficiency) = 30% (0.3); m (mass of gasoline taken) = 200 g (0.2 kg).

Constants: ρb (gasoline density) = 710 kg / m3; q (beats heat of combustion of gasoline) = 4.6 * 10 ^ 7 J / kg.

The engine operating time due to the use of 200 g of gasoline is expressed from the formula: η = Ap / Q = N * t / (q * m), whence t = η * q * m / N.

Calculation: t = 0.3 * 4.6 * 10 ^ 7 * 0.2 / 3660 = 754 s = 12 min 34 s.

Answer: A glass of gasoline will last for 12 minutes 34 from the operation of the gasoline engine.