Physics 40 Lab 1: Introduction to Excel & Graphing
Equipment: Decimal Scales, 100 Pennies
Group Lab Report
You will hand in one lab report for the group. Open a word document for your lab report. Make sure you
include the following at the beginning of your report (you do not need a title page):
1. Printed names of all in group
2. Date and Lab section
3. Lab number and Title
4. Computer station number you used.
You will use Excel to analyze your data but you will copy and paste the data and graphs back into the word
document to make a nice lab report. Include any calculations asked for. Answer questions in clear and
complete sentences. You can copy and paset the questions into your report and the answer them. Be brief
but thorough. Have the instructor check your report before you turn it in.
Experimental Procedure: Excel and Graphing
As an exercise in graphing data, you will graph the number of pennies versus the total mass of the
pennies.
0. Question 1: What sort of functional relationship do you expect between the total mass (y variable)
and number of pennies (x variable)? That is, how does the total mass depend on the number of pennies?
Do you expect it to be constant? Linear? Quadratic? Exponential? What do you expect and why?
Getting the Data
1. Make a 2-column table in Excel for your data, with the number of pennies in the left column and the
total mass in the right. Label your columns including units.
2. Measure the total mass (grams) of pennies using the decimal electronic scale for 1-20 pennies.
3. Question 2: What is the uncertainty in a single measurement? Does the uncertainty change as you
increase the number of pennies in your measurement? If so, how?
Part 1. Graphing the Data
1. Highlight the two columns of data
and then click on the graph icon.
2. Chose XY Scatter, highlight the sub-type WITHOUT lines
connecting the data points and then click on Next .
3. Click on the Series menu.
4. In the Name menu type: Mass of pennies versus number of
pennies.
5. In the X and Y values sections make sure you are plotting the
left column (number of pennies) along the x-axis versus the
right column (total mass) along the y-axis. Press Next.
6. For the X axis title type: Number of pennies and for the Y axis
title type: Mass of pennies(gr) and press NEXT.
7. Choose As new sheet and press finish. You should see your graph with the data plotted.
Part 2: Curve fitting the Data
1. From the chart menu choose Add Trendline.
2. Choose Linear.
3. Click on Option menu, check mark Display
Equation and Display R-squared on chart and
press OK. Expand the size of the equation box so
it is nice and large. Move it so it is not blocking
any portion of the graph or data.
4. Click on the graph legends (right of the graph) and delete it.
5. Click on the entire graph and from the Edit menu choose Copy.
6. Paste your graph into your word document lab report.
Part 3: Analyzing and Predicting from the Graph
1. Question 3: What is the slope and what does it mean? Predict the total mass for 100 pennies from
your plot of 20. Explain your reasoning.
2. Measure the mass of 100 pennies. Put both values your Excel Spread Sheet, properly labeled.
3. Calculate the following and show your calculations (you can do them by hand) and put your final
results in the spread sheet, properly labeled and don’t forget units.
1. Difference between predicted and measured mass for 100 pennies.
Experimental - True
x100
2. % Error
(Take the measured mass as True.)
True
4. Question 4: How does your prediction compare to the measured value for the mass of the 100
pennies? Do they agree within your experimental uncertainty?
5. Question 5: Is the relationship linear? What does the R-squared value mean? Look it up online and
explain it and how it relates to your result.
6. Copy and paste your excel table and graph into your Word Doc.