size of round through hole having straight side non tapered wall is inserted into the middle of this sealed box and a single perfectly elastic ball is injected into the box with a fixed velocity in an ideal situation the ball will be colliding with the walls while maintaining its momentum and speed after a finite time period the ball will pass through the hole in the partition numerous times and spend equal time on the two halves of the box 3 altering the second scenario by changing the round and straight through hole with a hole shaped like a funnel with the smaller opening of the stem end just larger than the diameter of the ball then the ball is likely to spend more time on the half with large cone shaped opening than the side with the smaller opening the reason is the ball will have a larger cross section higher probability to have the correct incidence angles up to 180 u00b0 to enter into the cone from the side with the smaller diameter end of the funnel stem and exit the partition to the other half than from the larger cone opening of the funnel side which was reduced from 180 u00b0 due to the funnel top inclining side angle this scenario is illustrated in fig1 4 now let us introduce more elastic balls into the box for the second situation with round non tapered through hole the balls will spend equal time on the two halves in other words at any give time there are likely equal numbers of balls in the two halves however for the third scenario.