Question

Определите КПД двигателя автомобиля, которому для выполнения работы 220,8 МДж потребовалось 16 кг бензина.

Answer 1

Ответ:

Дано:

Aπ = 220,8 МДж
q = 4,6 умножить на 10⁷ = Дж/кг
m = 16 кг
Найти:
η - ?
СИ:
220,8 МДж умножить на 10⁶ Дж
Решение:
η = Aπ
_______ 100%
Q

1) Q = qm = 4,6 * 10⁷ Дж/кг умножить на 16 кг
Q = 736 умножить на 10⁶ Дж
2) η = 220,8 умножить на 10⁶ Дж
_________________________ 100% = 30%
736 умножить на 10⁶ Дж

Answer 2

Calculating the Efficiency of the Car Engine

To calculate the efficiency of the car engine, we can use the formula for efficiency, which is given by:

Efficiency = (Useful energy output / Energy input) * 100%

In this case, the useful energy output is the work done by the engine, which is 220.8 MJ, and the energy input is the energy provided by the gasoline, which is 16 kg.

Calculating Energy Input from Gasoline

To calculate the energy input from the gasoline, we can use the energy content of gasoline. The energy content of gasoline is approximately 44 MJ/kg.

Using this information, we can calculate the energy input from the gasoline:

Energy input = Mass of gasoline * Energy content of gasoline

Energy input = 16 kg * 44 MJ/kg

Energy input = 704 MJ

Calculating Efficiency

Now that we have the useful energy output and the energy input, we can calculate the efficiency of the car engine using the formula mentioned earlier:

Efficiency = (Useful energy output / Energy input) * 100%

Efficiency = (220.8 MJ / 704 MJ) * 100%

Efficiency ≈ 31.36%

So, the efficiency of the car engine is approximately 31.36%.