The graph
A position-time graph tells a whole motion with no formula at all, and it reads with two rules: the steeper it is, the faster; flat means stopped. What almost everyone gets wrong the first time is reading it as a picture of the route — a rising curve gets mistaken for a hill — when what rises is the distance covered, not the ground. Nothing is calculated here: you look, and you say what happened.
Where this sits
- Comes after
- Quantities
- Opens up
- Motion
Exercises from this rung
Generated by the app, from easiest to hardest
What did it do at the end?
- Come back the other way
- Stop completely
- Speed up forwards
- Carry on the same
Why The curve goes down: the distance from the start is shrinking, so it is coming back. And beware the usual mistake: the curve does not draw the ground, it draws how far has been covered.
easierWhat is it doing?
- Accelerating the whole time
- Going at a constant speed
- Slowing down gradually
- Stopping and starting
Why Each stretch is steeper than the last: every second it covers more than the one before. And beware the usual mistake: the curve does not draw the ground, it draws how far has been covered.
in betweenWhen was it stopped?
- Between second 2 and 4
- Between 4 and 6
- Between 0 and 2
- It was never stopped
Why The flat stretch is standing still: time passes and the distance does not change. And beware the usual mistake: the curve does not draw the ground, it draws how far has been covered.
harder