A100 kg gymnast comes to a stop after tumbling. her feet do -5000j of net work to stop her. use the work-kinetic energy theorem to find the girl's initial velocity when she began to stop?

10 m/s

Explanation:

The work-kinetic energy theorem states that the net work done on an object is equal to the change in the kinetic energy of the object.

In formula:

(1)

where

W is the work done

Ki is the initial kinetic energy

Kf is the final kinetic energy

In this problem, we have:

the net work done on the gymnast

is the mass of the gymnast

is the final velocity of the gymnast, so her final kinetic energy is also zero:

Therefore, we can rewrite eq.(1) as

where is the initial velocity of the girl. By substituting the numbers and re-arranging the equation, we find: