m = 4 kg.
g = 9.8 m / s ^ 2.
h = 2.5 m.
The work of force A, when lifting the body, is determined by the formula: A = F * h, where F is the force under which I lift the load, h is the height of the load.
The force F with which the load is lifted, according to Newton’s 3 law, is equal to the force of gravity m * g: F = m * g.
The formula for determining the work will take the form: A = m * g * h.
A = 4 kg * 9.8 m / s ^ 2 * 2.5 m = 98 J.
Answer: when lifting the body, work is done A = 98 J.
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.