The value of the slope on a position-time graph indicates the object's velocity, or rate of change of position over time. Positive slope indicates the object is moving in the positive direction (e.g., right or up), while negative slope indicates it is moving in the negative direction (e.g., left or down). A steeper slope indicates a faster velocity, while a flatter slope indicates a slower velocity. Finally, a slope of zero indicates that the object is at rest.
