Free falling objects accelerate downward at a rate of approximately 10 m/s/s (or 9.8 m/s/s). As they move upward towards their highest point, they slow down. And as they fall downward from their highest position, they speed up. While the speed (and velocity) undergo these changes, the acceleration remains a constant value and is always directed downward.
 

Free-falling objects accelerate downward as they fall. In this question, you must identify the dot diagram that corresponds to a free-falling object. Three options are provided: a constant speed option, a slowing down option, and a speeding up option. You must identify the speeding up option since a free-falling object speeds up as it falls.

Be sure to "read the diagram" from top to bottom since that is the direction that the falling object is moving. When objects speed up, they cover a greater and greater distance in each consecutive second of time. For this reason, the spacing between dots increases as the object falls.