Position-time graphs show how an object's position changes over time. The slope of the graph represents velocity. Here are four common types of motion:
The position increases linearly over time. This means the object moves in a positive direction at a constant rate. The slope of the graph is positive and constant.
The position decreases linearly over time. This indicates motion in the negative direction with constant speed. The slope is negative and constant.
The graph is a curve that gets steeper with time. The object's velocity is increasing in the positive direction, so the slope is increasing.
The graph is a curve that becomes flatter with time. This means the object is slowing down while moving in the positive direction, or accelerating in the negative direction.