If a frictional force acts on the child, what is the magnitude of the mechanical energy dissipated by this force, if the speed of the child at the bottom is 9.7 m/s

Mechanical energy is 1411.35 N.

Explanation:

It is given that, the speed of the child at the bottom is 9.7 m/s, v = 9.7 m/s

We need to find the mechanical energy dissipated by force. The mechanical energy is equal to the sum of its kinetic energy and the potential energy. We know that at the bottom, height is equal to 0. The mechanical energy is thus equal to the kinetic energy.

Let mass of child is 30 kg

So, the mechanical energy dissipated by force is 1411.35 J.  

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures