1. Graphing / Using Graphs To illustrate what happens during the course of an experiment is done with a graph. Graph = a visual display of information of data. Slope = steepness, the ratio of vertical to horizontal change

2. Slope=Rise Run Rise = change in “y” (vert.) axis/variable Run= change in “x” (horz.) axis/variable Ratio of vertical change : change horizontal

3. Dependent and Independent Variables Manipulated or Independent variable = causes a change in the other variable. ****Y axis/vertical axis**** (length of time, speed) Responding or Dependent variable = a factor whose value changes or depends upon the value of the manipulated/ independent variable. ****X axis/ horizontal **** (amount of temperature, damage)

4. Independent Variable X Axis Dependant Variable Y Axis

5. Line Graphs Line graphs are used to show trends or how the data change over time. Adjacent points are related with a straight or curving line.

6. Line Graphs The dependent variable is plotted on the vertical y-axis. The independent variable is plotted on the horizontal x-axis.

7. Graphs Show Change In Figure 2-10, two things are changing, or varying – time and temperature. Time the independent variable. Its value does not depend on changes in the other variable, temp. Temperature is the dependent variable. Its value depends on changes in time.

8. A bar graph is used for comparing information collected by counting

9. Bar Graphs A bar graph is useful for comparing information collected by counting. In a bar graph, the bars are not connected.

10. Circle Graphs Circle or Pie Graphs show how a fixed quantity is broken down into parts. The circle represents the total. The slices represent the parts as percentages.

12. SI Use in the U.S. Where do we use SI other than in science?? Athletics = meters Medicine = mg. & ml. Soft drinks = L

13. Benefits Easy to convert powers of 10 One time cost Ready for trade to other countries