Idea 6of 6Builds onSteep means fastWhere she is
Higher, or steeper
Two lines, one graph: who is ahead, who faster?
Today you'll discover
- why being in front is not being faster
- what two crossing lines share, and what they do not
- the two readings that keep ahead and faster apart
Think firstTwo runners, one instant: who is winning?
Runner A is ahead; runner B's arrow is longer. Who is faster right now?
Decide first, then press Next. Compare the arrows, then the places, then the lines.
Two runners on a ground line marked in metres, one ahead with a short velocity arrow and one behind with a long one. After a prediction, the frames step one second at a time until the runner behind draws level. Then a position–time player draws two lines, the steeper one pulling ahead. The last step asks what two crossing lines share.
See the whole ideathe big idea and the key word, in one place
The big idea
Higher is ahead. Steeper is faster. Crossing is the same place.
Easy to get wrongA runner can be ahead and slower at once. The lead was earned earlier; the speed is what is happening now.
About this modelThe arrow is how fast and which way, not how far ahead.
The arrow is how fast and which way, not how far ahead.
Ready to use it?
- Say who is ahead, who is faster and where they meet from two lines on one graph.