G Dear ©2010 – Not to be sold/Free to use Stage 4 Year 9 Graphs of Physical Phenomena Time and Distance Graphs Press Ctrl-A G Dear ©2010 – Not to be sold/Free to use

Time-Distance Graphs Cars do not change speed instantly. Cars change speed gradually.

Average speed over a distance. Time-Distance Graphs Average speed over a distance. Time Distance B D A T Distance Average Speed = Time D S = T 3

Average speed over a distance. Time-Distance Graphs Average speed over a distance. A | 1hr 2hr 3hr 4hr 5hr 6hr 7hr 8hr 9hr 10km- 20km- 30km- 40km- 50km- 55-45= -10km 2hr B 7-5= -10 S = 2 = -5 km/h 4

Instantaneous speed at a point. Time-Distance Graphs Instantaneous speed at a point. Time Distance D T Distance Instantaneous Speed = Time D S = T 5

Instantaneous speed at a point. Time-Distance Graphs Instantaneous speed at a point. | 1hr 2hr 3hr 4hr 5hr 6hr 7hr 8hr 9hr 10km- 20km- 30km- 40km- 50km- 25-55 = -30km 8-6= 2hr -30 S = 2 = -15 km/h 6