1. Chapter 8 – Mapping Space and Time 8.1 - Journeys We will find out:  that speed is distance over time; v = s / t ;  that speed can be calculated from the gradient of a distance–time graph;  the meanings of average and instantaneous speeds and how these are calculated from speed–time graphs;  the meaning of the area under a speed–time graph and how to estimate this.

3. Speed and Velocity Speed = Distance Travelled / Time Taken = m/s IT IS A SCALAR QUANTITY – IT ONLY HAS MAGNITUDE Velocity = Distance Travelled / Time Taken = m/s IT IS A VECTOR – IT HAS MAGNITUDE AND DIRECTION Distance Speed x Time

6. Distance Time Graph Time (s) Distance (m) Moving at constant speed Stationary Constant speed but faster than A Moving back towards start point What else can we calculate from the graph?

7. Plot a Distance Time Graph for 1 marble journey…

8. Distance Time Graph Time (s) Distance (m) Gradient = Distance /Time = Speed Or dy / dx But it is different at different places?

9. Instantaneous Speed Time (s) Distance (m) What is the speed here? Calculate the gradient of the TANGENT on your graph The Gradient at this point is the INSTANTANEOUS SPEED

10. Average Speed Time (s) Distance (m) What is the AVERAGE Speed for the whole journey? Calculate the gradient of the CHORD on your graph The Gradient of the CHORD is the AVERAGE SPEED

11. Try this What is the instantaneous speed here

12. Try this

13. Try this What is the average speed between 40 and 60 mins?

14. Try this

19. Write these into your book with answers… For each of the graphs in question 2, calculate the distance travelled overall.

20. To recap on last lesson, answer these in the back of your book… Distance travelled is area under graph…

21. Making a Velocity Time Graph…