Experiment #2 Resistor Statistics The object of this experiment is to generate a histogram demonstrating how many resistors in a sample of the same nominal value meet specifications. A histogram is a plot that shows how many of an item fall into specific “bins”.

Procedure Each student will be given a sample of resistors having the same nominal value. For each resistor: Determine the nominal value from the color code. Measure and record the resistance of each resistor in the sample. Enter your data in an Excel table as shown on the next page. Plot a histogram bar graph of the measured values and determine the mean and the standard deviation of the resistance values.

Example Histogram Raw Data Table Generated by Excel Value 1 1000 2 1050 3 990 4 1075 5 950 6 899 7 1102 8 1080 9 1005 10 1020 Number of resistors with values < or = to 900 Bin Frequency 900 1 950 1000 2 1050 3 1100 More Number of resistors with values from 1051 through 1100 Plot of Excel Table Data

Data for Experiment #2 = Explain Allowable range, mean and standard deviation

Preparing to Plot a Histogram Before you start to generate a plot, create a sequence of 5 numbers in your Excel sheet, equally spaced, from the minimum of your allowable range to the maximum of your allowable range. For example, if the range was 400-800, I would generate the following sequence: 400 500 600 700 800

Generating a Histogram Table Click on the “Data” pull-down menu Select “Data Analysis” Select “Histogram” For Input Range Enter the cell range with your resistance measurements (e.g. a4:a20) For Bin Range Enter the cell range of your 5 values For Output Range Enter the cell that you want to be the upper left corner of your histogram table

Generating a Histogram Plot Select (click and drag the cursor over) the table that was created using the histogram command Click on the “Insert” pull down menu Select “Column” Select chart type You’ll see a preview of your plot, click “next” Enter a label for the x axis and change the plot title from “frequency” to something with your nominal resistor value in it, click “next” Select “as object in sheet 2” in last step then click “finish”

What needs to be turned in A printout of the data table including: The original data The histogram table The histogram plot