the second ball.
Pinboard box experimentBut of course you cannot let the ball go from exactly the same position with
exactly the same velocity and force. In reality, there will be a very slight
difference which you might not even be able to measure. The result is the ball-
bearing may take a very different route to the bottom and probably end up in a
different slot.
A simple pendulum
The free pendulum is one of the simplest mechanical systems to analyse. As
the pendulum swings back and forth, it gradually loses energy. The displacement
from the vertical and the (angular) velocity of the bob decrease until it is
eventually stationary.