Hello, dear friend, you can consult us at any time if you have any questions, add WeChat: daixieit

PHYS-310 Lab01b – Resistors!

Materials:

· 100[kΩ] Resistor Ribbon

· Screwdriver

· 9[V] Battery (if necessary)

· Fluke 87V DMM

Lab Objectives:

· Learn that your body has a widely varying resistance depending on the measurement conditions.

· Exhibit proper technique for making resistance measurements with a DMM.

· Make repeated accurate measurements.

· Learn to generate an histogram.

· Understand that component values have a tolerance.

Introduction

Resistors are among the most common circuit components used in electronics. They are used to impede the flow of current in an electrical circuit. Because of this property, there are many ways in which a resistor can be used to modify signals in a circuit or be used as a model for other physical phenomena. We will explore these behaviours in the future.

In this lab, we will focus on measuring resistors properly. We also learn that no component is perfect and thus must be assigned a tolerance.

Resistors are a circuit branch that has two nodes. There are different symbols for resistors – the “US” version and the “IEC” version:

 

 

 

 

 

Resistors are labelled according to a resistor color code. The color code may be useful for quickly identifying a general range for a resistor, but we will almost always measure the resistance using a Digital Multimeter (DMM) to find the resistance more precisely (and hopefully more accurately). Please see the appendix for the resistor color code.

Activity #1 – DMM Initial Setup and Measurement Matters!

Procedure:

1. Locate a screwdriver set, DMM and DMM Probes.

2. If necessary, install a new 9[V] battery in your DMM.

3. Plug the Black DMM probe into the “COM” terminal and the Red DMM probe in the ���️VΩ terminal.

4. Turn the DMM’s Multiselector to the resistance measurement “Ω” setting.

5. Touch the probe tips together. What happens? The DMM will show a number of resistance. And the resistance will increase generally.

Enter your Response Here

6. Hold the measurement probes in each hand with the metallic tips touching your fingers lightly. What is the nominal resistance of your body? The range of resistance is from 8,06. If there is a range, please feel free to use the ± symbol to indicate an “uncertainty” in the resistance through your body.

Enter your Resistance Measurement Here [Ω]:8.06+or-0.03

7. Now hold the metallic tips of your DMM probes tightly. Did the measurement change? Yes What is the “new” measurement of your body’s resistance?

Enter your Measurement [with units!] Here1.85+or-0.01

8. We are going to measuring a bunch of 100[kΩ] resistors. Assuming that we have a “perfect” 100[kΩ] resistor, calculate the total resistance of this resistor if measured “in parallel” with your body’s resistance. Recall that for two resistors in parallel, the total resistance is:

 

9. Enter your Calculation Here94.87kΩ=9.487*10^4Ω

10. What is the measurement error for this configuration? That is what is  for this configuration?

Enter your Calculation Here-5.13

11. Find your ribbon of 100[kΩ] resistors. Measure a single resistor with your body in parallel with the resistor. What is the resistance?

Enter your Measurement Here100.2kΩ

12. Now measure this resistor with just the metal probe tips. What is the resistance?

Enter your Measurement Here100.8kΩ

13. Use one or two sentence(s) to describe an appropriate measurement procedure for measuring a single resistor.

Enter your Response Here, when your measure this resistance, you should try your best to take away the resistance.

Activity #2 – Pete, Repete, Peat, Repeat, Piet…

Procedure:

1. Work with a partner to measure and record the resistance values of one-hundred 100,000[Ω] resistors for each partner (i.e. two-hundred total). Record your results in, Ohms [Ω], in the appropriate “tab” in the google spreadsheet found here. Please try not to overwrite anyone else’s data!

2. Open Excel and Install the Analysis ToolPak if you haven’t already done so.

a. Click on: File→Options→Add-ins→Manage: Excel Add-ins “Go…”

b. Check the “Analysis ToolPak” box and click OK.

c. I don’t know, you may need restart Excel for the Analysis Toolpak options to populate.

3. Watch the histogram tutorial.

4. Copy your resistance data (feel free to use others’ data too, if you want more statistics!)

5. Generate 10 “bins” for an histogram:

a. Find the minimum resistance value using the =MIN() function

b. Find the maximum resistance using the =MAX() function

c. Find =(MAX()-MIN())/10

d. Use this bin separation to generate a set of bins.

6. Generate an histogram of your data

a. Click on: Data→Data Analysis→Histogram→OK

b. The “Input Range” is your data

c. The “Bin Range” are your bins

d. Select “Chart Output”

e. Format and label your histogram then copy and paste in the space below

Copy your Histogram Here!

Questions:

1. Calculate 5% of 100,000[Ω]. Now find the range in which there are acceptable values of resistance for this resistor. Report your number as 100,000[Ω]±range.

Enter your response here.

 

2. Are all your measured values within this range?

Enter your response here.

Appendix

The Resistor Color Code: