Question

Шофер вимкнув двигун автомобіля при швидкості 72 км/год. рез 3,4 с автомобіль зупинився. Сила тертя коліс по асфальту дорівнюе 5880 H. Визначте імпульс автомобіля в момент вимкнення двигуна. Яка маса автомобіля?

Answer 1

Ответ:

с

м фото
Объяснение:

Answer 2

To determine the impulse of the car at the moment the engine is turned off, we can use the principle of conservation of momentum. The impulse is equal to the change in momentum of the car.

Given information:

- Speed of the car (v) = 72 km/h = 20 m/s - Time taken to stop (Δt) = 3.4 s - Frictional force between the wheels and the road (F) = 5880 N

Calculation:

The impulse (J) can be calculated using the formula:

J = Δp = m * Δv

where: - J is the impulse - Δp is the change in momentum - m is the mass of the car - Δv is the change in velocity

Since the car comes to a stop, the change in velocity (Δv) is equal to the initial velocity (v) because the final velocity is 0.

Therefore, Δv = v - 0 = v.

Substituting the given values into the formula, we have:

J = m * v

To find the mass of the car (m), we need to rearrange the formula:

m = J / v

Now, let's calculate the impulse and the mass of the car.

Calculation:

J = m * v = 20 m/s * Δt = 20 m/s * 3.4 s = 68 kg·m/s

The impulse of the car at the moment the engine is turned off is 68 kg·m/s.

To find the mass of the car, we can rearrange the formula:

m = J / v = 68 kg·m/s / 20 m/s = 3.4 kg

The mass of the car is 3.4 kg.

Please note that the mass of the car seems unusually low. It is possible that there may be a mistake in the given information or calculation.