1. Chapter 1 The Nature of Science 1.3 Communicating With Graphs
PHYSICAL SCIENCE
Chapter 1 The Nature of Science
1.3 Communicating With Graphs

2. 1.3 Communicating With Graphs Objectives
Identify three types of graphs and explain the ways they are used.
Distinguish between dependent and independent variables.
Analyze data using the various types of graphs.

3. A Visual Display A graph is a visual display of information or data.
Graphs make it easier to understand patterns by displaying data visually.
Different graphs use different methods for displaying data.

4. Line Graphs
A line graph can show any relationship where the dependent variable changes due to a change in the independent variable.
Line graphs usually show how a relationship between variables changes over time.
It is important to choose an appropriate scale for the graph.
The independent variable should be placed on the x-axis, the dependent variable on the y-axis.
Units must be consistent on a graph.

5. Table 4/Figure 18 pg. 23 Time A B C 16 5 17 16.5 10 19 15 20 21 17.516 5 17
16.5 10 19 15 20 21
17.5 23 18 25
18.5
Temperature °C
Time (min)

6. Bar Graphs
A bar graph is usually good for comparing information collected by counting, or comparing quantities.
Each bar represents a quantity counted at a particular time or a quantity of a particular type.
The independent variable should be plotted on the x-axis and the dependent variable on the y- axis.

7. Table 5/Figure 20 pg. 25 Number of Students Number of Classrooms 20 121 3 22 23 2 24 25 5 26 27

8. Circle Graphs
A circle graph (pie graph) is used to show how some fixed quantity is broken down into parts.
The circular pie represents the total.
The slices represent the parts and are usually expressed as percentages.

9. Figure 21 pg. 26