To what height was a load weighing 160 N lifted on a deck 8 m long if 800 J was done?

To what height was a load weighing 160 N lifted on a deck 8 m long if 800 J was done? What force did you have to apply to the load?

P = 160 N.

S = 8 m.

A = 800 J.

h -?

F -?

The work A of the force F, which acts in the direction of movement of the body S, is determined by the formula: A = F * S.

F = A / S.

F = 800 J / 8 m = 100 N.

If the friction force is neglected during the movement of the load, then the work of the force A is equal to the change in its potential energy ΔEp: A = ΔEp.

The change in the potential energy of the body ΔЕп is expressed by the formula: ΔЕп = m * g * h.

We express the weight of the body P by the formula: P = m * g.

ΔEp = P * h.

A = P * h.

h = A / P.

h = 800 J / 160 N = 5 m.

Answer: under the action of a force F = 100 N, the load was lifted to a height of h = 5 m.