Question

равномерно поднимая груз весом 100Н с помощью несмазанного неподвижного блока,рабочий прикладывает силу 150Н.каков КПД этого блока?пожалуйста напишите решение подробно

Answer 1

F- сила рабочего

Р- вес груза

n -КПД

КПД-коэфф. полезного действия, т.е. та часть силы, которую прикладывает рабочий для поднятия груза. В задаче использовался неподвижный блок - видимо сила трения верёвки об блок настолько велика, что рабочему приходится тратить свои дополнительные силы на преодоление этой силы трения (блок не смазан). Засчёт этого тратится больше силы - 150 Н вместо 100Н. Поэтому КПД находится так

n*F=P

n=P/F= 100Н/150Н= 0,66 

Ответ: 0,66 

Answer 2

Calculation of Efficiency

To calculate the efficiency of the block, we need to determine the work input and work output.

The work input is the product of the force applied by the worker and the distance over which the force is applied. In this case, the force applied by the worker is 150 N.

The work output is the product of the weight of the load and the distance over which the load is lifted. In this case, the weight of the load is 100 N.

To find the efficiency, we can use the formula:

Efficiency = (Work output / Work input) * 100%

Let's calculate the work input and work output first.

Calculation of Work Input

The work input is given by the formula:

Work input = Force * Distance

Since the force applied by the worker is 150 N, we need to find the distance over which the force is applied. Unfortunately, the distance is not provided in the question. Without this information, it is not possible to calculate the work input accurately.

Calculation of Work Output

The work output is given by the formula:

Work output = Weight * Distance

Since the weight of the load is 100 N, we need to find the distance over which the load is lifted. Unfortunately, the distance is not provided in the question. Without this information, it is not possible to calculate the work output accurately.

Conclusion

In order to calculate the efficiency of the block, we need to know the distances over which the force is applied and the load is lifted. Without this information, it is not possible to determine the efficiency.