Position-time graphs are essential in physical science because they provide a visual representation of an object's motion over time. These graphs illustrate the position of an object at various time intervals, allowing scientists and students to analyze an object's speed, direction, and acceleration.
The best summary of the reason for using position-time graphs would be:
"Position-time graphs are used in physical science to visually represent and analyze the motion of objects, enabling the determination of speed, direction, and acceleration over time."