Question

Совершает ли ученик механическую работу, опускаясь на лифте с верхнего этажа здания на первый?

Answer 1

Лифт совершает а вот человек нет

Answer 2

Can a student perform mechanical work by descending in an elevator from the top floor of a building to the first floor?

Yes, a student can perform mechanical work by descending in an elevator from the top floor of a building to the first floor. When an object moves against a force, work is done. In this case, the force opposing the motion of the elevator is gravity. As the elevator descends, gravity acts on the student and the elevator, causing them to move downward. The force of gravity does work on the student, and as a result, the student performs mechanical work.

It's important to note that the amount of work done by the student depends on the distance traveled and the force exerted. The work done can be calculated using the formula: Work = Force x Distance x cos(theta), where theta is the angle between the force and the direction of motion. In this case, since the force of gravity acts vertically downward and the motion is also vertical, the angle between the force and the direction of motion is 0 degrees, and cos(0) = 1. Therefore, the formula simplifies to Work = Force x Distance.

Please keep in mind that the work done by the student is only in the downward direction. If the elevator is moving at a constant speed, the net work done by the student is zero because the upward force exerted by the elevator cancels out the downward force of gravity.