Unit Plan Title: Electric Circuits – Charging Minds
Date: March 18/19/22, 2010
Candidate: Brian Turkett
Cooperating Teacher: Orlando Marrero
Grade Level: 9th-12th (General Physics)
Duration: 150 minutes
Lesson Plan Title: Resistance
1. Lesson Content (concept map encouraged)
Connections
What
Unit: Previous
Resistance is the opposition a device offers to the flow of
related
electric current. Resistivity is a characteristic of a material that topics/skills
depends on its electronic structure and temperature. A resistor
is a device designed to have a definite amount of resistance.
Resistance is strongest when the wire is the longest and
thinnest
Electric Current
Measuring current
Unit: Future
related
topics/skills
Current flow
Real-world Applications
Connections
Course: Previous
related
topics/skills
What
Charge
Conduction
Bridge to Today
The rate at which charge
passes a given point in a
circuit, is always conserved
in same amount of time, so
long as no additional
charge is supplied or no
charge is subtracted from
the circuit.
Measuring current in and
out of each junction.
Series – single path
Parallel – multiple
branches/paths
Household circuits are set
up in parallel. Christmas
lights are set up in series.
Bridge to Today
Electric charge is provided
by a source (cell, battery)
and this charge flows
through circuits in different
ways depending on the
number of paths possible.
The transfer of charge from
a charged object to a
neutral object. In this
lesson it is the transfer
through a conducting wire.
Course: Future
related
topics/skills
Thermodynamics
Temperature of a wire.
Microphones
Sound pressure changes
the position between a
metallic membrane and
solid back plate. Charging
happens due to waves
changing these separations.
2. Goals
1. Students will understand that resistance is affected by the length of a wire, the cross-sectional area of a wire, and the material of the wire.
2. Students will understand that the highest resistance will come from the longest and thinnest wire, so long as the material is the same.
3. Students will understand that the current, potential difference, and resistance are related by Ohm’s Law.
“Big Idea”:
Resistance is the opposition to the flow of electric current.
Expected stumbling blocks . . .
Resistivity
Addressed How?
Students will have trouble understanding the resistivity of a wire.
Resistivity charts will be provided on example pages and practice
worksheets.
Students will have trouble analyzing proportions such as doubling the
length or area of a wire, and its impact on resistance. Multiple
examples will be provided.
Proportions
3. Objectives (Given X,
SWBAT Y, as demonstrated by Z)
4. NYS/National Standards
(cut and paste complete standard)
1. Given a can of Play-doh, students will be
able to vary the length and area of the
Play-doh and measure the current and
voltage of the Play-doh in a circuit using a
multimeter.
4.1l All materials display a range of
conductivity. At constant temperature,
common metallic conductors obey Ohm’s Law.
Connections (described)
Students will be measuring
the length and calculating
the area of their Play-doh
4.1m The factors affecting resistance in a conductor are
cylinders. They will also be
length, cross-sectional area, temperature, and resistivity.
measuring the voltage and
Process skills:
ix. use measurements to determine the resistance of a circuit current that runs through
there Play-doh. This data
element
x. interpret graphs of voltage versus current
will help them to
xi. measure and compare the resistance of conductors of
understand resistance with
various lengths and
Assessments
(e.g. quiz, HW)
Play-doh Lab
regards to the conductivity
of the Play-doh.
cross-sectional areas
2. Given Regents questions and a
calculator, students will be able to
calculate resistance, resistivity, length, or
cross-sectional area using the resistance
equation, as demonstrated by Mr. Turkett
in example problems.
5. Assessment Attached
(name [ F or S])
4.1m The factors affecting resistance in a conductor are
length, cross-sectional area, temperature, and resistivity.
What Counts
(as evidence for understanding)
Students will be provided
Resistance/Resis
with an equation and a chart tivity Worksheet
of resistivities. From the
information provided in the
questions students will need
to calculate resistance,
resistivity, length of a wire,
or the area of a wire.
Example
(sample student language)
Play-Doh Lab [F]
Students will have completed the graphs
and made general statements that analyze
their data results. These statements
should reflect that current and voltage
relate to each other directly, and that
length and area affect the voltage and
current of the Play-doh in some way.
As voltage increases the current
increases.
Resistance/Resistivity [F]
Students will have completed the
worksheet and received at least a 6 out of
10.
As the wire length is doubled the
resistance doubles. As the area of the
wire doubles the resistance halves.
How will you use these
results?
These results will be used
during discussion of
resistance in the
powerpoint. Students will
offer what they found and
we will discuss why their
results might contradict
or confirm what science
holds as right.
Students answers to the
example questions will
help me assess how well
they understand my
powerpoint slides, my
explanations, and the
concepts of resistance.
This knowledge can be
used to show that my
approach helps their
understanding, or that I
may need to offer more
reinforcement in future
lessons.
Resistance Powerpoint [F]
Students will answer example questions
that split up the topics in the presentation.
The resistance is measured in ohms.
Students answers to the
example questions will
help me assess how well
they understand my
powerpoint slides, my
explanations, and the
concept of resistance. This
knowledge can be used to
show that my approach
helps their understanding,
or that I may need to offer
more reinforcement in
future lessons.
Formative Assessment
Contribution to the Summative Assessment?
Play-doh lab
Resistance/Resistivity
Resistance Powerpoint
Provides graphical analysis of voltage and current as well as resistance vs. length and resistance vs. area.
Allows students to calculate resistance, resistivity, length of a wire, or cross-sectional area of a wire.
Provides graphical analysis of voltage and current as well as resistance vs. length and resistance vs. area.
Allows students to calculate resistance, resistivity, length of a wire, or cross-sectional area of a wire.
6. Community Knowledge and Experience:
In what specific ways do you “HEAR” student voices?
Student voices will be heard through the sharing of their results of their Play-doh lab during the powerpoint. We will collectively assess why
some students received different results from what science states and why others confirmed these results. Students will be able to offer their
voice as well during the Play-doh lab as they are analyzing their graphs and data to understand what is happening in the Play-doh and circuit.
How will you USE what you “HEAR”?
These voices will be used to strengthen the concept of resistance and the nature of science. Students will see the importance of procedures
and accuracy of data collection.
How do you JOIN your students in shared experiences as a participant?
I will join the students by helping them build graphs and scaling their axes. I will ask guiding questions to promote critical thinking of these
results having students make statements surrounding the length and area of their play-doh and how this relates to their voltage and current.
Time
7. Procedure/ Transitions
Strategies for maximizing ontask engagement
Obj.
# (s)
8. Resources (what and
how distributed)
Back-up Plans
3 min
Bellwork
Day 1:
If it takes 8 Joules of work to
move a charge of 2 coulombs
around a circuit, then what is
the potential difference in the
circuit?
As students walk in the bellwork
will be placed on the back table.
Students will pick it up and work on
the answering the question. When
they have completed the question
they will bring it up to the front of
the room and place it in their
respective class folder.
7 min
Transition
I will transition into explaining that
today we are going to be starting a
lab that uses Play-doh. The purpose
of the lab is to roll the play-doh out
into cylinders. You will be placing
the play-doh into a circuit. We want
to vary the length or thickness of the
play-doh in each trial. You want to
conduct four trials. For each trial
you need to measure the current
going into the play-doh, the voltage
across the play-doh, the length
between your voltage
measurements, and the area of your
cylinder. You will need to calculate
area by measuring the diameter and
using this equation to calculate the
area. The materials you will need
are listed on the smart board. We
will be using 9 volt batteries so
please be careful when connecting
your circuits. Do not leave your
circuit connected for more than a
minute. This means you should be
taking your voltage and current
measurements simultaneously, or as
quickly as possible.
Bellwork sheets
Powerpoint
3 wires
2 multimeters
2 nails
1 battery
1 Play-Doh color
1 Ruler
1 calculator
If powerpoint is
down, then bellwork
will be written on
the whiteboard. If
bellwork sheets are
lost then students
can write their
answer on a
separate sheet for
the day.
90
min
3 min
Play-doh lab
Bellwork
Day 2:
If you made a cylinder of PlayDoh and measured the
diameter of the cylinder to be 2
cm, then what will the crosssectional area of the Play-Doh
cylinder be?
3 min
Bellwork
This lab will take at least two full
1.
class periods to finish. Students will
need to make sure they are
measuring length and diameter in
centimeters and converting these
measurements to meters. Area
calculations will need to use the
diameter of the cylinders. Voltage
and current measurements should
be made simultaneously and then
the circuit should be disconnected
in order to avoid burning the Playdoh and heating up the 9 volt
battery.
Students may need help with scaling
their graphs and drawing best fit
lines.
As students walk in the bellwork
will be placed on the back table.
Students will pick it up and work on
the answering the question. When
they have completed the question
they will bring it up to the front of
the room and place it in their
respective class folder.
As students walk in the bellwork
will be placed on the back table.
Students will pick it up and work on
the answering the question. When
they have completed the question
they will bring it up to the front of
the room and place it in their
respective class folder.
3 wires
2 multimeters
2 nails
1 battery
1 Play-Doh color
1 Ruler
1 calculator
Play-doh lab
Bellwork sheets
Powerpoint
Bellwork sheets
Powerpoint
If there is additional
time, have students
graph their data on
a computer and
have the computer
draw a best fit line.
If powerpoint is
down, then bellwork
will be written on
the whiteboard. If
bellwork sheets are
lost then students
can write their
answer on a
separate sheet for
the day.
If powerpoint is
down, then bellwork
will be written on
the whiteboard. If
bellwork sheets are
lost then students
can write their
answer on a
separate sheet for
the day.
2 min
Transition
30
min
Resistance Powerpoint
1 min
Transition
I will transition into explaining that
today we are going to be taking
notes on resistance and resistivity.
The play-doh in our lab acted as a
resistor and so we want to
understand what that means. I will
then ask them to take out their
notebooks.
I will begin by explaining that the
2.
resistor is the object (play-doh) that
contributes the action of resistance
due to the innate character of
resistivity it possesses. This means
that different wires have different
resistances because they can be
made up of different metals or have
different shapes that affect
resistance. In fact, play-doh colors
have different resistivites which is
probably caused by the metal
characteristics in their dyes.
I will then provide the students with
the equation for resistance and we
will look at graphs of resistance
versus length and resistance versus
area to understand that the highest
resistance is when we have the
longest and thinnest wire.
We will then work on examples
using this resistance equation.
When you walked in you picked up
a resistance and resistivity practice
worksheet. Take that out and work
on finishing that up for the
remainder of class. When you are
finished turn it into the class folder.
2.
Powerpoint, notebooks, pen,
calculator
Resistance worksheets will
be placed next to the
bellwork at the beginning of
class.
15min
Resistance/Resistivity
Students will work on a worksheet
2.
Resistance/resistivity
that asks them to calculate
worksheet, pen, calculator,
resistance, resistivity, length of a
wire, or cross-sectional area of a
wire. I will place a resistivity chart
up on the smartboard for students
to reference.
What affordances and limitations if any have you considered with respect to resources (time, money, learning curve of equipment use, ect)?
I have afforded two class periods for students to finish the play-doh lab. This gives them the time to learn how to graph their data accurately
and analyze these graphs to understand the relationships of length, area, voltage, and current to resistance.
9. Applications, Connections and Extensions:
What are you going to ask students to do that gives them a chance to use this new knowledge (should make connections, should go out of the
classroom)?
Students will be able to extend their knowledge that all appliances have some resistance. Household appliances possess some resistance
inside all of them. The calculators the students are using also use resistance. Students can connect resistance to the idea of a four way highway
moving into one lane, or a pipe decreases its diameter. Students can apply their knowledge of resistivity to why certain metals are used for
circuits and appliances.
10. Inclusive Instruction:
How are you meeting diverse student needs (e.g. multiple modalities, small group work, culturally diverse examples)?
The lab will be completed in small groups and the worksheet provides both graphical as well as written explanations and answers. The lab
also requires the use of technology and physical manipulation of materials. If students can complete either the graphical or written
assignment alone, then this could be enough for me to assess their learning and understanding of the material and areas that may need
reinforcement.
Profile three students who represent unique needs in your class (IEP’s, ESL, enrichment, marginalized students) AND
describe how you will meet their needs.
1. Amina Zatar
Amina is an ESL student and may need some
extra help understanding the language. I
provided visuals on the sheet to help her see
what the words are describing. If she
requires more assistance Mr. Marrero can
2. Cyd Marie Rodriguez – ESL (Spanish
speaking)
I have provided picture aids in most of my
documents with arrows that point to the
necessary steps in order to layout a visual aid
for those students who cannot read English
3. Jemere Singleton
Jemere needs to be separated from some of
the students in the classroom. He has been
working with one student really well and I am
continuing to place those two together. If this
partner of his is absent one of the days then
translate for her, or I will walk her through
the instructions.
well. I also have her working with a group of
boys who understand the material well and
are good at communicating with her.
Jemere rarely does his work and causes
disruptions. On these days he needs more of
my one on one attention and aid.
12. Safety
What are your safety considerations?
Students will be using 9 volt batteries. Students are to make sure that when using these batteries they do not leave them connected to a circuit
for too long. All measurements should be taken simultaneously so that circuits can be disconnected immediately after measurements are
recorded. If students leave the batteries connected for too long they could become hot and burn the play-doh or damage the wires.
How will you know the students understand the safety procedures?
I will provide detailed instructions prior to each of the activities and ask after each of my instructions whether anyone has any questions. I will
also ask for confirmation through yes/no or thumbs up/down or head shakes whether people get the activities.
11. Reflections
How did you construct a meaningful learning environment?
This lesson extended the knowledge of current, conservation of charge, and voltage to resistance. Students participated in an inquiry based lab
experiment that asked them to manipulate the length and thickness of Play-doh cylinders. The lab had them graphing, analyzing these graphs,
measuring voltage, current, length, and calculating area and slope. There are numerous scientific standards that this single lab addresses.
Furthermore the powerpoint provides a through discussion of the scientific knowledge of resistance upon which students could compare their
results. This provided a fruitful dialogue of feedback and response that stimulated understanding and learning.
What are the strengths and limitations of this lesson?
The strengths of this lesson include the numerous scientific standards that the lab addresses. Students use measuring skills, calculating skills,
graphing skills, and analyzing skills. There is also a sense of curiosity as to why we are connecting Play-doh into a circuit. The limitation of this
lesson is the consistency in measuring and accuracy of student calculations and graphing. Another limitation of this lesson focuses on the idea
of resistivity. Students found this concept hard to understand and did not understand why different Play-doh colors have different resistivities
like different metals do.
How could this lesson be revised?
I will need to revise the lab statements. I want students to calculate V/I for each trial and not the slope of their graphs. Also I will need to
include a section for students to record their diameters and then calculate area. The purpose of calculating rho could be stated as well.
What insights have you learned about your students?
I was really pleased to see how well my students could graph. A lot of my colleagues have found difficult in this aspect, and I decided to try it.
My students did have trouble with creating a scale and drawing best-fit lines, but those issues were easily solved by having groups collaborate
their knowledge and experiences.
What insights have you learned about yourself?
I learned that I like to try new things, and that I can adapt easily to any mishaps that happen in my lab write-up and still get great results from
the students. Also, I’m really glad I included the graphs and had the students calculate resistance. I think the general class can handle all of this.