1 of 26 Copyright © AQA and its licensors. All rights reserved. Graphs Mathematics for GCSE Science

2 of 26 Copyright © AQA and its licensors. All rights reserved. Objectives

3 of 26 Copyright © AQA and its licensors. All rights reserved. Introduction Science would be a lot harder without graphs. In pairs… Without drawing a graph, use the information in the table to decide if the pH of water affects the number of tadpoles that develop from frogspawn. pH of waterNumber of tadpoles

4 of 26 Copyright © AQA and its licensors. All rights reserved. Introduction What conclusion did you reach? This is what a graph of the information would look like. This suggests that tadpoles’ development was affected by the pH of water and that they were more likely to develop when the pH was around 6.5. pH of water Number of tadpoles

5 of 26 Copyright © AQA and its licensors. All rights reserved. You have to be able to read values from a graph

6 of 26 Copyright © AQA and its licensors. All rights reserved. What do each of these lines have in common? Straight Parallel Same gradient Upwards slope Gradient of 2

7 of 26 Copyright © AQA and its licensors. All rights reserved. Straight Cross at one point What do each of these lines have in common?

8 of 26 Copyright © AQA and its licensors. All rights reserved. What does the equation of a straight line mean? The gradient of the line.

9 of 26 Copyright © AQA and its licensors. All rights reserved. How is the gradient calculated? Click for equation 3 1

10 of 26 Copyright © AQA and its licensors. All rights reserved. How is the gradient calculated? -2 1 Click for equation

11 of 26 Copyright © AQA and its licensors. All rights reserved. How is the y -intercept calculated? It is the where the line crosses the y -axis.

12 of 26 Copyright © AQA and its licensors. All rights reserved. Match each line to its equation There will be two equations left over.

13 of 26 Copyright © AQA and its licensors. All rights reserved. What does the tangent on a curve represent? A curve has an infinite number of tangents. Each one has a different gradient. Each one represents the rate of change of the variable at that point. Gradient

14 of 26 Copyright © AQA and its licensors. All rights reserved. What does the area under a curve represent? It depends on what the graph represents! The area under a velocity/time graph gives displacement. The area under speed/time graph gives distance. The area under an acceleration/time graph gives velocity.

15 of 26 Copyright © AQA and its licensors. All rights reserved. Some questions to try from Exampro GCSE Maths F

16 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Maths F

17 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Maths F

18 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Maths F

19 of 26 Copyright © AQA and its licensors. All rights reserved.

20 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Biology sample assessment materials

21 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Biology sample assessment materials

22 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Physics sample assessment materials

23 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Physics sample assessment materials

24 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Physics sample assessment materials

25 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Chemistry sample assessment materials

26 of 26 Copyright © AQA and its licensors. All rights reserved. GCSE Chemistry sample assessment materials