Question

Подъёмный кран поднимает равномерно груз массой 200 кг на высоту 20 г за 10 с. какую мощность развивает подъёмный кран? ответ представьте в кВт

Answer 1

A(работа) = mgh = 200*20*10 = 40000Дж

N = A/t = 40000/20 = 2000 Вт или 2 кВт

Ответ: 2кВт

Answer 2

Calculating Power Developed by the Crane

To calculate the power developed by the crane, we can use the formula:

Power (P) = Work done (W) / Time taken (t)

The work done in lifting the load is given by the formula:

Work (W) = Force (F) × Distance (d)

Given: - Mass of the load (m) = 200 kg - Height (h) = 20 m - Time taken (t) = 10 s

First, let's calculate the work done in lifting the load.

Calculating Work Done

The force required to lift the load is equal to the weight of the load, which can be calculated using the formula:

Force (F) = Mass (m) × Acceleration due to gravity (g)

The acceleration due to gravity is approximately 9.81 m/s^2.

Using this information, we can calculate the force and then the work done.

Calculating Force and Work Done

The force required to lift the load: F = m × g F = 200 kg × 9.81 m/s^2 F = 1962 N

The work done in lifting the load: W = F × d W = 1962 N × 20 m W = 39240 J

Calculating Power

Now, we can calculate the power developed by the crane using the work done and the time taken.

Power (P) = Work done (W) / Time taken (t) P = 39240 J / 10 s P = 3924 W

So, the power developed by the crane is 3924 watts (W), which can be represented in kilowatts as 3.924 kW.