1. How to get top marks for a graph Here are some typical graphs, some of which contain errors. Can you spot them? Simulation of head acceleration during an accident

2. So what is a graph then? Generally, it is a clear visual representation of dependent vs. independent variable(s) ‘Clear’ means good contrast and scale. Independent variables are ones you change. Dependent variables are nature’s reply – the ones you choose to observe.

3. How are my graphs graded? The most common and perhaps most important graph in science is a two axis graph with a best-fit line. To score top marks when doing these graphs you must include: A very detailed title with dependent, independent and even one or two control variables - the same as for data tables Labelled x- and y-axes with units No joining of dots, but a best-fit line or curve to be able to see any trend and to make predictions

4. Place the labels and line in the correct place Graph of oxygen volume vs. Time for Elodea at 20°C in direct sunlight Time (min) Volume of O 2 (cm 3 )

5. Now you know how, open a new page & practice using the following data: Absorbance (A)Time (s) 10,30 8,110 6,520 5,030 4,640 3,550 2,760 2,070 1,580 Change of absorbance with time for 5 drops of Blackberry juice in 3mL of 0,1M bleach solution

6. You should get something like this:

7. And one more thing… If you are doing a graph on paper then be sure to draw your data crosses and best-fit line in pencil

8. To know more about graphing see: Mr. Thompson’s You Tube video on Graphing How to insert a best-fit line How to plot two y-axes on the same graph Pencil graphing, choosing a scale etc.