After one second of falling, a ball’s velocity is about 10 meters per second downward. So why does it travel only about 5 meters downward during that one second?
If the ball traveled steadily at 10 meters per second downward for one second, it would travel 10 meters downward. But a falling ball does not move steadily. Instead, it accelerates downward and its velocity changes with time. When dropped from rest, its velocity starts at 0 and steadily increases to about 10 meters per second downward after 1 second of falling. Its average velocity during that 1 second interval is only about 5 meters per second (the average of 0 and 10 meters per second) downward. Therefore, the ball only moves downward about 5 meters.