A box with nails, the weight of which is 54 kg, is lifted to the fifth floor of a house under construction
| December 7, 2020 | education
A box with nails, the weight of which is 54 kg, is lifted to the fifth floor of a house under construction, with the help of a movable block acting on a cable 360 newtons. Calculate the plant efficiency.
Efficiency = A useful / A spent
And useful = 54 * 10 s J – the work of moving the box to a height s – height of 5 floors
And spent = 360 * 2 * s, here 2 s, because the movable block gives a loss in the length of the cable
Efficiency = 0.75 = 75%
Answer: 75%
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.
