Communicating with Graphs Physical Science In science, we use a lot of graphs This graph shows the temperature changes in the Pacific Ocean The year (time ) is plotted on the x axis The temperature is plotted on the y axis Graph of light from Pluto • The wavelength is on the x axis • The albedo (light intensity) is on the y axis methane Graphs are useful to analyze information • Stockmarket - bargraph Electrocardiogram – EKG – measures heart function on a line graph Pie graphs – hmm sounds tastey! • Each set of data has a piece of the pie! Line Graph Acivity Activity: Plot the temperature of your ice water. * Write the Title “ The Cooling Curve of Ice Water” • Label the horizontal (x) axis – time (seconds) • Label the vertical (y) axis – temperature ( Celsius) • Plot points - The points or dots on the graph show data • Connect the points – The lines connecting the points give estimates of the values between the points. • Use different colored lines for each set of data Bar Graphs • Bar graphs useful for comparing information collected by counting • Useful for counting number of items at a particular time (x axis) Bar Graph Activity • Make a bar graph of the following information • Title: Number of Students in Physical Science • X axis: 1st period; 2nd period; 3rd period; 4th period; 5th period and 6th period. • Y axis: number of students (1-30) • 1st period = 21 • 2nd period = 17 • 3rd period = 29 • 4th period = 22 • 5th period = 22 • 6th period = 27 Circle or Pie Graphs • Used to show some fixed quantity broken into parts To create a circle graph • 1) Divide the data for each type by total • 1st period = 21 21/138 = • 2nd period = 17 17/138 = • 3rd period = 29 29/138 = • 4th period = 22 22/138 = • 5th period = 22 22/138 = • 6th period = 27 27/138 = • Total students = 138 • 2) Multiply that fraction by 360o • 21/138 * 360 = angle of the circle Review • Where is the x axis? • Where is the y axis? • On what axis is time usually plotted? • Which is the independent variable? • Which is the dependent variable?