Define motion entirely as a change in position relative to a chosen reference point over time.
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Hook about relative distances.
Defining reference points.
If you want to measure a distance, you have to decide where to start. When distance is stated with respect to a fixed object or point, that fixed point is called a reference point.
Visual of houses, school, and garden.
When measuring distance, the answer depends entirely on your starting location.
How reference points determine motion.
An object is in motion if its position changes with respect to a reference point with time. If its position is not changing compared to that same reference point, it is said to be at rest.
Comic showing a bus passenger's perspective.
Motion is never absolute; it always depends on the observer's reference point.
Scenario testing rest vs motion.
You are sitting on a fast-moving train reading a book. Which of the following statements is true based on your choice of reference point?