Michigan Test for Teacher Certification (MTTC) Secondary Integrated Science Practice test

What primary factor distinguishes distance from displacement?

1. The magnitude of motion

2. The direction of motion

3. The type of object in motion

4. The acceleration of the object

The correct answer is: The direction of motion

The primary factor that distinguishes distance from displacement is the direction of motion. Distance is a scalar quantity that measures the total length of the path traveled by an object, without regard for the direction. In contrast, displacement is a vector quantity that accounts for both the magnitude and the direction of the motion, representing the shortest straight-line path from the initial to the final position of the object. For example, if an object moves in a circular path and returns to its starting point, the distance traveled is the length of the circular path, while the displacement is zero because the initial and final positions are the same, indicating no change in position despite the distance traveled. This difference in how each term incorporates direction is fundamental to their definitions, illustrating why direction is the key distinguishing factor between distance and displacement.