Explanation:
gravitational potential energy at the top of the hill, which transforms into kinetic energy as he moves bottom of the hill
that's mean potential energy transfoms into kinetic energy
It transfers the electrical current from the point of contact on the lightning rod into the ground.
The speed of the ball just before impact was v=√(2gh) = 6.26m/s. The acceleration is twice this over the time (twice because the second speed is the same in the other direction, meaning the total change in speed is 2V)
a = 12.52/0.10 = 125.2m/s²
The force is F=ma, so F = 0.5kg·125.2m/s² = 62.6N