A body weighing 100 kg lies on the floor of an elevator, which rises vertically upwards at an equal
September 27, 2021 | education
| A body weighing 100 kg lies on the floor of an elevator, which rises vertically upwards at an equal time with an acceleration of -2m / s². Determine body weight.
Given:
m = 100 kg – body weight;
a = -2 m / s ^ 2 – the acceleration of the elevator (directed downwards against the movement of the elevator);
g = 10 m / s ^ 2 – acceleration of gravity.
It is required to find P – body weight.
Since the force of gravity is directed downward and the acceleration is also directed downward, then Newton’s second law in this case will look like this:
– m * g + N = – m * a – where N is the support reaction force, numerically equal to the weight P. Then:
P = N = m * g – m * a = m * (g – a) = 100 * (10 – 2) = 100 * 8 = 800 N.
Answer: body weight will be 800 N.
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.