Question

Який ккд двигуна автомобіля, якщо під дією сили тяги 994 Н він проїхав 9,6 км, витративши 1 л бензину

Answer 1

Работа 
A=F*S = 994 * 9600 ≈ 9,54*10⁶ Дж = 9,54 МДж

Масса литра бензина:
m=ρ*V=700*1*10⁻³=0,7 кг
Сжигаем бензин:
Q=q*m = 46*10⁶*0,7=32,2*10⁶ Дж = 32,2 МДж

КПД = A/Q*100% = 9,54*100%/32,2 ≈ 30 %

Answer 2

Calculating the Car's Engine Efficiency

To calculate the car's engine efficiency, we can use the formula:

Engine efficiency = (Work output / Energy input) * 100%

Where: - Work output is the work done by the car, which is the force of traction multiplied by the distance traveled. - Energy input is the energy provided by the fuel, which can be calculated from the fuel consumption.

Calculating Work Output

The work output can be calculated using the formula:

Work output = Force of traction * Distance traveled

Given: - Force of traction = 994 N - Distance traveled = 9.6 km

We need to convert the distance from kilometers to meters for consistency. 1 km = 1000 m, so 9.6 km = 9600 m.

Now we can calculate the work output: Work output = 994 N * 9600 m

Calculating Energy Input

The energy input can be calculated from the fuel consumption. In this case, the car traveled 9.6 km and consumed 1 liter of gasoline.

The energy content of gasoline can be taken as approximately 34.2 MJ/liter.

So, the energy input from 1 liter of gasoline is: Energy input = 34.2 MJ

Engine Efficiency Calculation

Now we can calculate the engine efficiency using the previously mentioned formula: Engine efficiency = (Work output / Energy input) * 100%

Substitute the calculated values: Engine efficiency = (994 N * 9600 m / 34.2 MJ) * 100%

Calculating this gives us the engine efficiency under the given conditions.