Question

Кран поднимает груз 20кН. Найти работу 5с при скорости 30м/мин

Answer 1

Кран поднимает груз F= 20кН. Найти работу t=5с при скорости V=30м/мин 
F=20 000 Н   V=0,5 м/с    A - ?

A=F*S=F*V*t=20 000*0,5*5=50 000 Дж=50 кДж

Answer 2

Calculation of Work Done by a Crane

To find the work done by a crane, we can use the formula:

Work = Force x Distance

In this case, the force exerted by the crane is 20 kN (kilonewtons) and the distance it lifts the load is 5 s (seconds) at a speed of 30 m/min (meters per minute).

First, let's convert the speed from meters per minute to meters per second. Since there are 60 seconds in a minute, we can divide the speed by 60 to get the speed in meters per second:

30 m/min ÷ 60 = 0.5 m/s

Now we can calculate the work done by the crane:

Work = Force x Distance

Work = 20 kN x 0.5 m/s x 5 s

To calculate the work, we need to convert the force from kilonewtons to newtons. Since 1 kN is equal to 1000 N, we can multiply the force by 1000:

20 kN x 1000 N/kN = 20,000 N

Now we can substitute the values into the formula:

Work = 20,000 N x 0.5 m/s x 5 s

Calculating the result:

Work = 20,000 N x 0.5 m/s x 5 s = 50,000 J (joules)

Therefore, the work done by the crane is 50,000 joules.