Question

Автомобиль массой 2т движется в гору. На участке пути длиной 37,5 м скорость его движения увеличилась от 5 до 10 м/с. Считая движение автомобиля равноускоренным, определите силу тяги его двигателя, если коэффициент сопротивления движению равен 0,02, а угол подъёма составляет 30 градусов.

Answer 1

F-µmg sinα=ma

V²-V₀²=2aS

a=(100-25)/75=1 м/с²

F=m(µg sinα+a)=2000(0.02*10/2+1)≈2000H

Ответ: 2000Н 

Answer 2

Calculating the Tractive Force of the Car's Engine

To calculate the tractive force of the car's engine, we can use the following formula for the force of traction in the case of uniform acceleration on an inclined plane:

F = m * (g * sin(θ) + a * cos(θ) + μ * (g * cos(θ) - a * sin(θ)))

Where: - F is the tractive force - m is the mass of the car (2 tons, which is 2000 kg) - g is the acceleration due to gravity (approximately 9.81 m/s^2) - θ is the angle of inclination (30 degrees) - a is the acceleration of the car - μ is the coefficient of resistance to motion (0.02)

Calculating the Acceleration of the Car

First, let's calculate the acceleration of the car using the given information about the change in speed and the length of the path.

The formula for calculating acceleration in the case of uniform acceleration is:

a = (v^2 - u^2) / (2 * s)

Where: - a is the acceleration - v is the final velocity (10 m/s) - u is the initial velocity (5 m/s) - s is the length of the path (37.5 m)

Using the given values: a = (10^2 - 5^2) / (2 * 37.5) a = (100 - 25) / 75 a = 75 / 75 a = 1 m/s^2

Calculating the Tractive Force

Now, we can use the calculated acceleration and the given values to find the tractive force.

F = 2000 * (9.81 * sin(30) + 1 * cos(30) + 0.02 * (9.81 * cos(30) - 1 * sin(30)))

Let's calculate the tractive force using the given values and the formula.

F = 2000 * (9.81 * 0.5 + 1 * 0.87 + 0.02 * (9.81 * 0.87 - 1 * 0.5)) F = 2000 * (4.905 + 0.87 + 0.02 * (8.517 - 0.5)) F = 2000 * (4.905 + 0.87 + 0.02 * 8.017) F = 2000 * (4.905 + 0.87 + 0.16034) F = 2000 * 5.93534 F ≈ 11870.68 N

So, the tractive force of the car's engine is approximately 11870.68 N.