[Home > Things Fall > Tennis Video]
Here is a video clip of a tennis ball being dropped straight down. Since falling objects are always being accelerated downwards by gravity, they are always falling faster and faster. This means there will NEVER be equal spacing between successive positions of the tennis ball. Check out the "overlap" frame to see this. The spacing between where the ball was, and where it is next, always gets larger and larger.
This "unequal spacing" seen in the "overlap view" is an important aspect of how things fall. You can also see this here if you answer "yes" for the ball's trail.