Let me walk you thru a session with my children on (un) teaching them basic concepts of speed and velocity… thru a series of posts.
At the end of the posts I will deconstruct the method behind this approach.
Scene 1: Luke Skywalker gets on his pod. He needs to get to the Sand Dunes on the planet of Tatooine. He travels north for 3 Kms. At the Dulcos pass he takes a left turn to go west. He then travels 5 Kms. At that point he suspects that the sand people may be stalking the area ahead. So he turns north again and travels for 7 Kms. He then reaches the Sand Dunes of Tatooine.
- Can you draw the journey? Make sure you draw the pod, sand people and the mountains. Any other aliens and planetary images get extra points 🙂
- How much did Luke travel in all?
- How much did Luke travel North? West?
Luke traveled a ‘distance‘ of 15 Kms in all. In the direction of North he only traveled 10 Kms. So the ‘displacement‘ is 10 Kms North. Similarly, his ‘displacement‘ west is 5 Kms.
Here is the picture from Star Wars on the two suns setting in the planet of Tatooine.
A shot of Luke Skywalker and his pod.
As the text book definition  goes:
Distance and displacement are two quantities that may seem to mean the same thing yet have distinctly different definitions and meanings.
- Distance is a scalar quantity that refers to “how much ground an object has covered” during its motion.
- Displacement is a vector quantity that refers to “how far out of place an object is“; it is the object’s overall change in position.
Displacement has a value and direction (called vector in physics). Distance just has value (called scalar). As we go along we will see why the distinction is needed.