 Today, you will learn how to:  Make a constant value a cell instead of a number    Create a scatter plot for your data Insert a trendline into your graph Format your graph with gridlines and axes titles

 First, you will enter your given set of data into an Excel spreadsheet.

 Make sure you put your mass value in it’s own cell. We will use this value as a constant in your equation.

 Usually, when you copy a formula, it will change the row/column as you copy the formula.

 To prevent this, put a $ in front of both the column letter and the row number (ex. $A$4)  Enter the force equation using the mass from the cell instead of typing the number

 As you can see in the picture below, the $ does not let the cell with the $ change:

 To calculate an average in Excel, you will want to type AVERAGE(), and put the cells you would like to average inside the parentheses.

 Excel also allows us to create graphs for data analysis  To graph, start by highlighting two columns of data  Click on the “Insert” tab, then click the scatterplot button.

 The first column you highlight will appear on the horizontal axis of the graph.

 The second column you highlight will appear on the vertical axis of the graph  For the majority of your graphs, you will want to graph points, not lines.

 Your graph should look like this:  You should delete both instances of “Force (N)” from the graph, since you will put titles under graphs. (Only delete the title if you have multiple sets of data on a single graph)

 Click on your graph  The “Chart Tools” menu will show  Select the “Layout Tab”  Click on the “Axes Titles” button to add horizontal and vertical axes titles.

 For the horizontal axis, your title should read “Radius(m)”  For the vertical axis, your title should read “Force (N)”

 You will also want to add both major & minor gridlines for both the horizontal and vertical axes  In the same menu, click the “Gridlines” button, then insert the appropriate gridlines on your graph

 Your graph should now look like this:

 Generally, when we take a set of data, we like to find an equation to model the data.

 To add a trendline, right click on a data point on your graph. Select “Add Trendline”.

 A menu will pop up. For this graph, you will select:   A linear fit Show equation on chart Do NOT select the “Set Intercept” button.

 Select close and move your equation so it can easily be read.  Your graph should look like this:

 Your trendline is given as a generic y vs. x graph, since Excel does not know the variables you used to produce the graph.

 When you present your data in your lab report, you should replace the y and x with the appropriate variables for your experiment.

 Example  F = 34.12r + 0.562

 Your graph should have a white background when you submit your report.

 This should be a default setting on Office 2007. However if you have a grey or another color background, you need to change the color to white.

 You can do this using the “Design” tab under the “Chart Tools” menu. Select a design with a white background.

 Just like your data table in your spreadsheet, you will want to copy and paste your graph into a Word file when you write your lab report.  Make sure your graph utilizes as much space as possible (~ ½ page) by clicking on a corner and dragging the image so it is larger.

 Make sure you type and center a title below the graph.

 Figure 1 – A graph of centripetal force vs. the radius of the hanging mass.

The End

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