Question

Сколько времени действует сила тяги 4 кН на автомобиль массой 3т если его скорость меняется за это время от 36км/ч до 54км/ч

Answer 1

Ответ и решение во вложении

Answer 2

Calculation of the Time Duration

To calculate the time duration for which a force of 4 kN acts on a car with a mass of 3 tons while its speed changes from 36 km/h to 54 km/h, we can use the formula:

Force (F) = Mass (m) × Acceleration (a)

The acceleration can be calculated using the formula:

Acceleration (a) = (Final Velocity (v) - Initial Velocity (u)) / Time (t)

Rearranging the formula, we get:

Time (t) = (Final Velocity (v) - Initial Velocity (u)) / Acceleration (a)

Given that the force is 4 kN, which is equal to 4000 N, and the mass is 3 tons, which is equal to 3000 kg, we need to convert the velocities from km/h to m/s.

Using the conversion factor of 1 km/h = 0.2778 m/s, we can convert the velocities as follows:

Initial Velocity (u) = 36 km/h × 0.2778 m/s = 10 m/sFinal Velocity (v) = 54 km/h × 0.2778 m/s = 15 m/s Now, we can substitute the values into the formula to calculate the time duration:

Time (t) = (15 m/s - 10 m/s) / Acceleration (a)

To find the acceleration, we can use Newton's second law of motion:

Force (F) = Mass (m) × Acceleration (a)

Rearranging the formula, we get:

Acceleration (a) = Force (F) / Mass (m)

Substituting the values, we have:

Acceleration (a) = 4000 N / 3000 kg = 4/3 m/s^2

Now, we can substitute the values of acceleration and velocities into the time formula:

Time (t) = (15 m/s - 10 m/s) / (4/3 m/s^2)

Simplifying the equation, we get:

Time (t) = 5 m/s / (4/3 m/s^2) = 15/4 s = 3.75 s

Therefore, the time duration for which a force of 4 kN acts on the car is 3.75 seconds.

Answer

The time duration for which a force of 4 kN acts on a car with a mass of 3 tons while its speed changes from 36 km/h to 54 km/h is 3.75 seconds.