Question

Работа двигателя автомобиля, прошедшего с постоянной скоростью путь 3 км, составляет 800 кДж. Определите силу сопротивления при движении автомобиляЧему равна мощность его двигателя, если время движения составило 3 мин?​

Answer 1

F - сила автомобиля, с которой он двигался

Fc - сила сопротивление

модули этих сил равны, т.е. Fc=F

A=FS - работа автомобиля

1)Fc=A/S=800000Дж/3000м=~267 Н

2) P=A/t=800000Дж/3мин×60==~4,4 КВт

Answer 2

Calculation of Resistance Force

To determine the resistance force experienced by the car, we can use the formula:

Work = Force × Distance

Given that the work done by the car's engine is 800 kJ and the distance traveled is 3 km, we can rearrange the formula to solve for force:

Force = Work / Distance

Substituting the given values, we have:

Force = 800 kJ / 3 km

Before calculating the force, we need to convert the units to a consistent system. Let's convert 800 kJ to Joules and 3 km to meters:

Force = 800,000 J / 3,000 m

Now we can calculate the force:

Force = 266.67 N

Therefore, the force of resistance experienced by the car is approximately 266.67 Newtons.

Calculation of Engine Power

To determine the power of the car's engine, we can use the formula:

Power = Work / Time

Given that the work done by the engine is 800 kJ and the time taken to travel the distance is 3 minutes, we can rearrange the formula to solve for power:

Power = Work / Time

Substituting the given values, we have:

Power = 800 kJ / 3 min

Again, we need to convert the units to a consistent system. Let's convert 800 kJ to Joules and 3 minutes to seconds:

Power = 800,000 J / 180 s

Now we can calculate the power:

Power = 4,444.44 Watts

Therefore, the power of the car's engine is approximately 4,444.44 Watts.