Question

12. A woman lifts a 35-kg child a distance of 1.5 m and carries her forward for 6.5 m.
How much work does the woman do in lifting the child?​

Answer 1

Answer:

515.025J

A woman lifts a 35-kg child a distance of 1.5 m and carries her forward for 6.5 m.

How much work does the woman do in lifting the child?​

Explanation:

Given;

Mass m = 35kg

Distance of lifting l = 1.5m

Acceleration due to gravity g = 9.81 m/s^2

Workdone = mgl = 35×1.5 × 9.81 = 515.025 J

Answer 2

The change in potential energy is equal to the work that must be done, to lift the child a certain distance. Therefore, the work done by the woman in lifting the child is:

$W=\Delta U\\W=mgh_f-mgh_0\\W=mg(h_f-h_0)\\W=35kg*1.5m(1.5m-0m)\\W=515.03J$