Making graphs in lab is very important because students may notice trends not easily seen in a column of data. All plots this semester, with the exception of histograms, will be scatter plots. Make sure NOT to use line plots which only allow one variable to be graphed against data point numbers.
Below there are two different ways to create graphs in Excel.
1. Highlight the data columns that you want to be graphed.
2. After highlighting the columns, click on the “Insert” tab and click on the option for a scatter plot (the “Scatter” button).
3. After clicking on the “Scatter” option, click on the option under “Scatter With Only the Markers” in order to create a graph without a line.
Sometimes there are circumstances when you need to plot multiple variables into a plot or need to switch the axis.
1. Click on the “Insert” tab and click on “Scatter” and then the option for the graph without the markers. A blank graph will be shown on excel.
2. Right click on the blank graph and click on “Select Data” to put data into the plot.
3. When the “Select Data Source” screen pops up, to add data to the plot, click on the “Add” button.
4. After clicking the “Add” button, the values for the x and y axis can be added to the graph. To add the x and y values to the graph, in “Series X values” line highlight the column for the x axis and for “Series Y values” highlight the values for the y axis.
5. To add more values to the graph, repeat step 4 for each of the x and y axis.
6. The graph should look like this when you are done.
Once a graph is made in Excel, finding an equation which accurately models the data is important to determining how the two variables in the graph are related.
In Excel, one can use the “Trendline Fit” feature to add a fitted equation line/curve to the graph. Excel uses statistical methods to find the parameters of the equation, allowing the to user to have a model equation for the data graphed. Users must make sure the line/curve fit matches well with the data points as not all data will be related by the same functional form. Always make sure to inspect the fitted line/curve to the data to determine if the model line/curve accurately predicts the data points.
1. In order to create the model equation, click on one of the points on the graph. Afterwards, right click and pick the option that says “Add Trendline”.
2. When the “Trendlines Options” box pops up, for this type of graph, because it is a linear line, click on “Linear”. There are other options for other types of graphs depending on what type of data you are collecting. After clicking on “Linear” for the trend line, to find out the equation of the line, click the option that says “Display Equation on chart”. This will show the equation of the trend line on the graph.
There are different methods for printing in Excel. Printing in Excel can be done by clicking on the print button but there can be times when everything is unable to fit onto one sheet of paper during lab class or while writing the lab report.
Why is this important?
Knowing different methods of printing is important because this allows you to be able to use different methods to point your spreadsheet during lab class. These methods are useful for times when you will be printing specific parts of your data or tables or to see whether or not you can print your work on a single piece of paper.
Method 1: Using Print Preview and the Home Icon
One way to print in Excel is to use the “Print” and then the “Print Preview” options. This method is similar to printing regularly in Microsoft Word.
1. This can be done by first pressing on the “Office” icon on the top of the page.
This button can be found above the menu bar.
2. After clicking on the “Office” icon, click on the “Print” option then on the “Print Preview” in order to preview how the data sheet will be printed out.
3. Oftentimes, the original page orientation setting on Excel is set to portrait. Having the setting on “Portrait” setting can sometimes cause part of the data collected during the experiment to be cut off.
4. In order to make sure all of the data collected onto a single sheet of paper, it is better to put the page orientation settings to “Landscape”.
Method 2: Using Print Area
Another method to print is to select a certain area to be used for printing. This help save paper when printing different parts of the lab, such as only the graphs, data collected, or to make sure all of the data or graphs created during lab need to be printed on a single sheet of paper. Also, this will help when trying to print a certain number of columns in the spreadsheet.
1. In order to set a specific area for printing, first highlight the area that needs to be printed on the excel spreadsheet. Afterwards, click on the “Page Layout” tab and on “Print Area” in order to create the printing area.
2. This will allow you to be able to set a specific area in the spreadsheet to be used for printing. The selected area will be shown on the “Print Preview” option.
Method 3: Page Scaling
Another way to print in Excel is to scale the worksheet for printing, either shrinking or enlarging the size of the spreadsheet in order to fit into the pages you want to print.
1. Under the “Page Layout” tab click on the button found on the bottom right corner of the “Page Setup” button. This will open a dialogue box which will allow you to be able to change the orientation, scaling, and margins of the sheet.
2. When the dialogue box opens, under the “Scaling” option, click on “Adjust to” and enter the percentage of the normal size that you want to change. Entering a percentage larger than 100% will cause the worksheet to become larger while entering a percentage smaller than 100% will reduce the worksheet to fit into the pages.
Note: The above step (#2) can also be done by adjusting the percentage in the “Scale to Fit” option next to “Page Setup”.
Creating equations in Excel will allow you to be able to use operators and create equations for lab. There are different functions built in Excel that can be used in various formulas; such as the average, sum, trigonometric functions, and the standard deviation. One can also name a cell, which can then be used throughout the spreadsheet without having to rewrite a certain constant or formula. Not only that, you can also reference a certain constant. By using a reference for the constant, this allows the constant to be able to be used in different parts of the spreadsheet without changing the value.
Why is this important:
Knowing how to write equations in excel is important when creating different formulas during lab. An important thing to remember is to use the equal sign (=) before starting any equation or when using an operator.
1. In order to create equations or use any operator, one has to write an equal sign (“=”) to indicate that what will be writing into the cell will be a formula. This will tell Excel that that will be followed by the “=” will be an operator rather than random numbers or words.
2. If you do not remember certain formulas, one can click on the “Formulas” tab. This is show different formulas that can be used in Excel in case you forget how to write a particular formula during class or at home while writing your lab report.
1. Trigonometric formulas (cos, sin, tan, etc) are, by default, in radians in Excel and need to be converted In order to convert from radians to degrees. This can be done by converting from degrees to radians by multiplying the radians angle by “π divided by 180″ (π/180).
2. In Excel, π is written as “pi()”
Creating axis labels will allow you to properly label your graphs.
1. To add labels on the graphs, click on the graph then on the “Design” tab, under “Chart Tools”. In the “Chart Layouts” box click on the first option, which will cause the title and x and y axis labels to be on the graph. Also under the “Design” tab, there are other options for changing the colors of the markers on the graph.
2. The title and x and y axis can be changed by double clicking on each of the boxes and writing the titles for each part of the graph.
3. Another way to add labels to the graph is by clicking on the graph and under the “Chart Tools” banner there is a tab that says “Layout”. After clicking on the layout tab, to add labels for the axis click on “Axis Titles” and for the title click on “Chart Title”.
4. The horizontal axis can is inserted to the graph by clicking on “Axis Titles” and then on the “Primary Horizontal Axis Title” tab. The horizontal axis can be added after clicking on “Title Below Axis” option, which will put the title for the horizontal axis under the graph.
5. The vertical axis can is inserted to the graph by following the previous step (step 9). Instead of clicking on “Primary Horizontal Axis Title” option, click on “Primary Vertical Axis Title” option. There are different options for the vertical axis to be added on the graph, but I prefer having the vertical axis label be inserted vertically rather than horizontally. The y axis label can be inserted sideways by clicking on “Rotated Title” option.
6. Inserting the Title can be done by clicking on the “Chart Title” option under “Chart Tools” and the “Layout Tab”. Clicking on the “Above Chart” option will put the title on the top of the graph.
This image shows how capacitors can be shown in series and in parallel, and how they can be combined to make calculations easier. Click the picture for more helpful info!