Notebook EP - Electric potential and fields draft
.docx
keyboard_arrow_up
School
Iowa State University *
*We aren’t endorsed by this school
Course
132L
Subject
Electrical Engineering
Date
Apr 3, 2024
Type
docx
Pages
14
Uploaded by MegaJayPerson927
Lab EP - Electric potentials and fields
During this lab you will explore the electric potential and electric fields produced by charged conductors with different geometries.
Major equipment
Large graphic tablet (this is in addition to the usual small tablet)
Custom-made plastic base with electric connections
Set of silver-ink prints on conductive carbon paper
Digital multimeter.
DC power source
The large drawing tablet is expensive and delicate. Treat it with care!
Lab EP – Page 1
Working with two tablets
Today, you will have two tablets on your table. The small tablet is for sketches, as usual. The large tablet will be used to collect data as described below.
1.
Setting up the apparatus
The apparatus to be used is depicted below. Both the power source and the voltmeter should be off for now. Check all the wiring in your setup. Make sure that the multimeter is set to function as a DC voltmeter before you turn on the power source.
Both devices can stay off until section 1.3.
The bottom surface of the plastic board is lined with rubber to protect the tablet. Use care when moving
the board, to avoid scratching the tablet.
Lab EP – Page 2
Do not drag the pen or the probe over the paper.
Avoid scratching the carbon paper and the silver electrodes.
Lift
and reposition the tip instead.
1.1.
The large drawing tablet
The drawing tablet for this experiment is much larger than the one we normally use in these labs. It will be used to record the location of the points where the potential is measured.
Download and double-click the Tablet Preferences
file. A dialog box will ask you if you want to continue: select “Replace”.
Download and open Blank canvas
. Maximize the window
so it takes the whole screen. (This is necessary to obtain the correct mapping between the tablet and the screen!)
On the left-hand corner of the screen, select “Layer 2”.
The stylus only writes when the lower button on the side of the pen is pressed. Otherwise, it just
moves the cursor around the screen. Test your pen: make some markings and check that the cursor correctly maps the motion of the pen on the tablet (left/right and up/down)
1
.
If not pre-selected, choose Paintbrush as your writing tool. On the top toolbar, set the Brush size
to 4. During today’s experiment, it will be useful to use different colors: click on the desired color on the color wheel before writing.
To erase, you may use the Eraser tool, or select the area and click Delete. 1.2.
The plastic board
A custom-made plastic board provides an easy way to
connect the electrodes to the power source. For this shortened version of the experiment, the electrode
sheet with two parallel lines has been pre-installed. If you
removed the sheet (don’t), you would see what is shown to
the right.
The parallel line electrodes are connected to sockets 4 and
5, which means each is connected to one of the terminals
of the power source.
1
The mapping should work fine when the button panel is on the right. If it doesn’t, just turn the tablet around!
Lab EP – Page 3
How to install an electrode sheet:
Find the sheet with two parallel straight lines. Describe
the 3D system that these 2D electrodes represent.
It represents two charges with an electric field between them.
Each sheet has a pre-punctured hole for each electrode. Thread a washer into each of the screws and then gently
insert the screws in the holes in the electrodes, doing your very best to not make the hole larger! The washer should lay between the head of the screw and the paper.
Place the paper on the board so that the
numbers are upright, and so that the screws
are aligned with the corresponding sockets.
Secure the screws without overtightening. The
washers should not protrude outside of the
silver painted area.
Once the electrode sheet is in place and the board is on the tablet, tap all four corners of the paper with the pen to make sure that the entire paper is being mapped onto the writable area. Adjust the position of the board on the tablet if needed. Do not drag the stylus over the paper (or the tablet!).
Avoid scratching the carbon paper and the silver electrodes. Lift and
reposition the tip instead.
1.3.
The power source and the multimeter
Make sure the multimeter is set to work as a DC voltmeter
Set the Range
of the multimeter to Auto
.
Turn on the power source and set the output to 10 V. Touch each of the electrodes with the pen. One of them should give a reading of 0 V, and the other a reading of about 10 V.
Adjust the output of the power source to exactly 10.0 V as read on the multimeter
(the multimeter
is a more reliable instrument than the voltmeter built into the power source).
Then, while the 10.0 V reading is on the screen of the multimeter, change the Range to Hold.
This will force the device to round values to only 2 significant figures, the appropriate precision in this experiment. Lab EP – Page 4
Whenever you measure potentials with the probe on one of the carbon paper samples, try to not rest your hands Also, avoid the using the probme right over
unused screw holes
–they produce bad data.
2.
The parallel electrodes
2.1. Potential and electric field in a conductor
Prediction: How does the potential depend on position for points on
one of the electrodes?
Potential depends on the distance between the electrodes and the charge of those electrodes.
Test it!
Place the probe at different locations on
each electrode (not around). Describe what you observe.
As we move away from negative charge, the potential increases towards the positive charge. What can you conclude about the electric field within the electrodes? Explain.
The field is going into the negative electrodes and out of the positive ones.
Lab EP – Page 5
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
Related Questions
By doing the " Coloumbs Law Lab " how do you calculate the electric force on suspended balloon and the charge on each balloon? Can you give an sample calculation
arrow_forward
1. The practical unit of electric charge.
2. A path for the current to flow.
3. DC Voltage has
4. Resistance to current flow in AC circuits, measured in ohms.
5-7. Types of grounds in electrical circuits.
8. Also known as Ohm's Law.
9. A quantity defined as amount of work done over time.
10. Types of material that has 4 valence electrons.
11. One Coulomb is equal to
12. Best conductor material type.
13. Best insulator material type.
14.The value of a resistor without considering its tolerance value percentages.
15. 1 picoampere (pA) is equal to
-polarity
electrons or protons stored in a dielectric.
ampere (A).
arrow_forward
The movement of electrical charge between two points in an electric circuit is a measure of what?
O Voltage.
Resistance.
O Current.
Rower
arrow_forward
Choose the correct answer.
*Please answer it ASAP if you can
arrow_forward
The 'skin effecť is a phenomenon experienced when current flows through a metal.
Which two of the following statements are correct?
15
Select one or more:
O a. A smaller 'skin depth' implies a higher resistance
O b. Direct current can cause the skin effect
O c. The skin depth is smaller in highly conductive metals
O d. The skin depth is larger in metals with high magnetic permeability
arrow_forward
Order the following four classes of materials from highest resistance to the flow of electric current to lowest resistance. (Use only ">" or "=" symbols. Do not include any parentheses around the letters or symbols.)
Insulators
Superconductors
Conductors
Semiconductors
arrow_forward
Determine the resistance of a bus bar of copper if the length is 75 feet long
and the diameter is 0.75 inch.
It is a Basics electrical subject.
arrow_forward
Use your research skills to find out about the recycling of metals, and the role of electromagnets.
Produce a leaflet for a recycling company that can be given to members of the public to teach them about recycling.
arrow_forward
give 2 examples of electrostatic devices with explanation
arrow_forward
Alternating current is __________.
Select one:
A. AN ALTERNATING FLOW OF ELECTRONS
B. ELECTRONS REVERSING THEIR FLOW AT REGULAR INTERVALS
C. THE MOST COMMONLY USED CURRENT
D. ALL OF THE ABOVE
arrow_forward
explain the relationship of the following electrical values:
Resistance and current
Electrical power and voltage
Electrical work and resistance
Electrical energy and voltage
Current and electrical power
arrow_forward
Current can not flow through an insulator because
they have
O a. free electrons
O b. no free protons
O c. no free electrons
O d. free neutrons
arrow_forward
Explain electrical conductivity with diagram
arrow_forward
What is the resistance of a
copper specimen with an
initial resistance of 250 ohms
at 38 degrees Celsius? Present
temperature is 48 degrees
Celsius and RTC at O degree
Celsius of 1/237.6 per degree
Celsius? *
Your answer
arrow_forward
b) chose from column A what is suitable for column B:
1-
2-
3-
4-
5-
A
Matter
Atom
Current
Resistance
Electricity
B
Is an invisible force that can produce
light, heat by attraction.
The opposition or restriction the flow of
charge and measured by ohm.
The rate of flow of charge and measured
by ampere.
Is generally described as anything that
has weight and occupies space.
Is the smallest particle to which an
element can be reduced.
arrow_forward
How you should be thinking about electric circuits? Explain the flow and give an example different from the slides provided.• Voltage • Resistance• Current
arrow_forward
The drawing shows a circuit that includes a bimetallic strip (made from brass and steel) with a resistance heater wire wrapped around it. When the
switch is initially closed, a current appears in the circuit because charges flow through the heater wire (which becomes hot), the strip itself, the
contact point, and the light bulb. The bulb glows in response. As long as the switch remains closed, does the bulb:
Resistance
Contact
heater wire
point
Brass
Steel
Switch
continue to glow
cannot be determined
flash on and off
eventually turn off permanently
arrow_forward
answer as soon possible
arrow_forward
draw the figure
write your soln neat and complete thank you
answer it in 1hr
arrow_forward
Trivia about electricity and how electricity help us in daily lives
arrow_forward
SEE MORE QUESTIONS
Recommended textbooks for you
Electricity for Refrigeration, Heating, and Air C...
Mechanical Engineering
ISBN:9781337399128
Author:Russell E. Smith
Publisher:Cengage Learning
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:9781337900348
Author:Stephen L. Herman
Publisher:Cengage Learning
Related Questions
- By doing the " Coloumbs Law Lab " how do you calculate the electric force on suspended balloon and the charge on each balloon? Can you give an sample calculationarrow_forward1. The practical unit of electric charge. 2. A path for the current to flow. 3. DC Voltage has 4. Resistance to current flow in AC circuits, measured in ohms. 5-7. Types of grounds in electrical circuits. 8. Also known as Ohm's Law. 9. A quantity defined as amount of work done over time. 10. Types of material that has 4 valence electrons. 11. One Coulomb is equal to 12. Best conductor material type. 13. Best insulator material type. 14.The value of a resistor without considering its tolerance value percentages. 15. 1 picoampere (pA) is equal to -polarity electrons or protons stored in a dielectric. ampere (A).arrow_forwardThe movement of electrical charge between two points in an electric circuit is a measure of what? O Voltage. Resistance. O Current. Rowerarrow_forward
- Choose the correct answer. *Please answer it ASAP if you canarrow_forwardThe 'skin effecť is a phenomenon experienced when current flows through a metal. Which two of the following statements are correct? 15 Select one or more: O a. A smaller 'skin depth' implies a higher resistance O b. Direct current can cause the skin effect O c. The skin depth is smaller in highly conductive metals O d. The skin depth is larger in metals with high magnetic permeabilityarrow_forwardOrder the following four classes of materials from highest resistance to the flow of electric current to lowest resistance. (Use only ">" or "=" symbols. Do not include any parentheses around the letters or symbols.) Insulators Superconductors Conductors Semiconductorsarrow_forward
- Determine the resistance of a bus bar of copper if the length is 75 feet long and the diameter is 0.75 inch. It is a Basics electrical subject.arrow_forwardUse your research skills to find out about the recycling of metals, and the role of electromagnets. Produce a leaflet for a recycling company that can be given to members of the public to teach them about recycling.arrow_forwardgive 2 examples of electrostatic devices with explanationarrow_forward
- Alternating current is __________. Select one: A. AN ALTERNATING FLOW OF ELECTRONS B. ELECTRONS REVERSING THEIR FLOW AT REGULAR INTERVALS C. THE MOST COMMONLY USED CURRENT D. ALL OF THE ABOVEarrow_forwardexplain the relationship of the following electrical values: Resistance and current Electrical power and voltage Electrical work and resistance Electrical energy and voltage Current and electrical powerarrow_forwardCurrent can not flow through an insulator because they have O a. free electrons O b. no free protons O c. no free electrons O d. free neutronsarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Electricity for Refrigeration, Heating, and Air C...Mechanical EngineeringISBN:9781337399128Author:Russell E. SmithPublisher:Cengage LearningDelmar's Standard Textbook Of ElectricityElectrical EngineeringISBN:9781337900348Author:Stephen L. HermanPublisher:Cengage Learning
Electricity for Refrigeration, Heating, and Air C...
Mechanical Engineering
ISBN:9781337399128
Author:Russell E. Smith
Publisher:Cengage Learning
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:9781337900348
Author:Stephen L. Herman
Publisher:Cengage Learning