1. Kinetic
He makes the ball move by kicking it, which increases the kinetic energy
Explanation:
Below is an attachment containing the solution.
We divide the thin rectangular sheet in small parts of height b and length dr. All these sheets are parallel to b. The infinitesimal moment of inertia of one of these small parts is

where

Now we find the moment of inertia by integrating from

to

The moment of inertia is

(from (-a/2) to

(a/2))
The battery will be full still a 8v bc of no time comparison