Current & Circuits Unit Plan

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Unit Lesson Plan – Current and Circuits
Teacher:
<Teacher>
Grade:
Time Frame:
9
School:
Subject:
NGSS DCI:
12 days
<School>
PSI Algebra Based Physics
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This unit provides necessary background and skills for the following
units.
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Essential Knowledge 1.B.1: Electric charge is conserved. The net
charge of a system is equal to the sum of the charges of all the
objects in the system.
a. An electrical current is a movement of charge through a conductor.
b. A circuit is a closed loop of electrical current.
Learning Objective (1.B.1.2):The student is able to make predictions,
using the conservation of electric charge, about the sign and relative
quantity of net charge of objects or systems after various charging
processes, including conservation of charge in simple circuits.
Essential Knowledge 1.E.2: Matter has a property called resistivity.
a. The resistivity of a material depends on its molecular and atomic
structure.
b. The resistivity depends on the temperature of the material.
Learning Objective (1.E.2.1):The student is able to choose and justify
the selection of data needed to determine resistivity for a given
material.
Essential Knowledge 4.E.4: The resistance of a resistor, and the
capacitance of a capacitor, can be understood from the basic
properties of electric fields and forces, as well as the properties of
materials and their geometry.
a. The resistance of a resistor is proportional to its length and
inversely proportional to its cross-sectional area. The constant of
proportionality is the resistivity of the material.
b. The capacitance of a parallel plate capacitor is proportional to the
area of one of its plates and inversely proportional to the separation
between its plates. The constant of proportionality is the product of
the dielectric constant, κ, of the material between the plates and the
electric permittivity, εo.
c. The current through a resistor is equal to the potential difference
across the resistor divided by its resistance R. The magnitude of
charge of one of the plates of a parallel plate capacitor is directly
proportional to the product of the potential difference across the
capacitor and the capacitance. The p lates have equal amounts of
charge of opposite sign.
Learning Objective (4.E.4.1):The student is able to make predictions
about the properties of resistors and/or capacitors when placed in a
simple circuit, based on the geometry of the circuit element and
supported by scientific theories and mathematical relationships.
Learning Objective (4.E.4.2):The student is able to design a plan for
the collection of data to determine the effect of changing the
geometry and/or materials on the resistance or capacitance of a
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AP Physics 1 and 2 Standards:
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Note that this exact Smart Notebook presentation has not been used in the classroom, although all of the
material has. The pacing below is approximate based on a 40-45 minute class period. Feel free to adjust as
necessary and please provide your feedback!
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circuit element and relate results to the basic properties of resistors
and capacitors.
Learning Objective (4.E.4.3):The student is able to analyze data to
determine the effect of changing the geometry and/or materials on
the resistance or capacitance of a circuit element and relate results to
the basic properties of resistors and capacitors.
Essential Knowledge 4.E.5: The values of currents and electric
potential differences in an electric circuit are determined by the
properties and arrangement of the individual circuit elements such as
sources of emf, resistors, and capacitors. physics
Learning Objective (4.E.5.1):The student is able to make and justify a
quantitative prediction of the effect of a change in values or
arrangements of one or two circuit elements on the currents and
potential differences in a circuit containing a small number of sources
of emf, resistors, capacitors, and switches in series and/or parallel.
Learning Objective (4.E.5.2):The student is able to make and justify a
qualitative prediction of the effect of a change in values or
arrangements of one or two circuit elements on currents and potential
differences in a circuit containing a small number of sources of emf,
resistors, capacitors, and switches in series and/or parallel.
Learning Objective (4.E.5.3):The student is able to plan data
collection strategies and perform data analysis to examine the values
of currents and potential differences in an electric circuit that is
modified by changing or rearranging circuit elements, including
sources of emf, resistors, and capacitors.
Essential Knowledge 5.B.9: Kirchhoff ’s loop rule describes
conservation of energy in electrical circuits. The application of
Kirchhoff’s laws to circuits is introduced in Physics 1 and further
developed in Physics 2 in the context of more complex circuits,
including those with capacitors.
a. Energy changes in simple electrical circuits are conveniently
represented in terms of energy change per charge moving through a
battery and a resistor.
b. Since electric potential difference times charge is energy, and
energy is conserved, the sum of the potential differences about any
closed loop must add to zero.
c. The electric potential difference across a resistor is given by the
product of the current and the resistance.
d. The rate at which energy is transferred from a resistor is equal to
the product of the electric potential difference across the resistor and
the current through the resistor.
e. Energy conservation can be applied to combinations of resistors
and capacitors in series and parallel circuits.
Learning Objective (5.B.9.1):The student is able to construct or
interpret a graph of the energy changes within an electrical circuit
with only a single battery and resistors in series and/or in, at most,
one parallel branch as an application of the conservation of energy
(Kirchhoff ’s loop rule).
Learning Objective (5.B.9.2):The student is able to apply
conservation of energy concepts to the design of an experiment that
will demonstrate the validity of Kirchhoff’s loop rule (∑∆V = 0) in a
circuit with only a battery and resistors either in series or in, at most,
one pair of parallel branches.
Learning Objective (5.B.9.3):The student is able to apply
conservation of energy (Kirchhoff ’s loop rule) in calculations involving
the total electric potential difference for complete circuit loops with
only a single battery and resistors in series and/or in, at most, one
parallel branch.
Essential Questions
(What questions will the student be able to answer as a result of the instruction?)
1. What are voltage, current, and resistance?
2. How are voltage, current, and resistance related?
3. What factors affect resistivity?
Knowledge & Skills
(What skills are needed to achieve the desired results?)
By the end of this unit, students will know:
 That current is defined as charge over time
 The relationship between voltage, current, and
resistance
 Ohm’s Law
 Kirchoff’s Rules (the rules will not be named but
they will be applied)
 The relationship between
voltage/current/resistance and power in circuits
 The relationship between emf and terminal
voltage
By the end of this unit, students will be able to:
 Use the following equations to solve problems
with simple DC circuits:
𝐼=
𝑄
𝑡
𝑅=
𝜌𝐿
𝐴
𝐼=
𝑉
𝑅
𝑃 = 𝐼𝑉 =
𝑉2
𝑅
= 𝐼2 𝑅
𝑅𝑒𝑞 𝑖𝑛 𝑠𝑒𝑟𝑖𝑒𝑠 = 𝑅1 + 𝑅2 + 𝑅3 + ⋯
1
𝑅𝑒𝑞 𝑖𝑛 𝑝𝑎𝑟𝑎𝑙𝑙𝑒𝑙
=
1
1
1
+
+
+⋯
𝑅1 𝑅2 𝑅3
𝑉𝑇 = 𝜀 − 𝐼𝑟
Assessment
(What is acceptable evidence to show desired results (rubrics, exam, etc.)? Attach Copy
During the Smart Notebook lesson designed to introduce concepts, students will be continually questioned on these
concepts using a combination of class work/homework questions and the SMART Response system. Classwork and
Homework questions will be discussed as a class and misconceptions will be addressed by the teacher prior to the
formal evaluations listed below.
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Ohm’s Law Lab Quiz
Series and Parallel Lamp Circuit Lab Quiz
Current and Circuits Test
Other assessments on the NJCTL website are optional and can be used as needed.
(What is the sequence of activities, learning experiences, etc, that will lead to desired results (the plan)?
Day
1
www.njctl.org
Topic
Classwork
Homework**
Current and Ohm’s Law
Presentation to slide 31
Problems 1-3 & 7-9
Problems 4-6 & 10-12
7th Grade PSI
Matter and Energy Flow
Note that this exact Smart Notebook presentation has not been used in the classroom, although all of the
material has. The pacing below is approximate based on a 40-45 minute class period. Feel free to adjust as
necessary and please provide your feedback!
2
Ohm’s Law Lab
Lab
Finish lab and
prepare for quiz
3
Ohm’s Law Lab Quiz +
Power
Quiz & Presentation to
slide 45 + Problems 21-26
Problems 27-32
4
Resistivity and Resistance
Presentation to slide 57 +
Problems 13-16
Problems 17-20 & MC 1-9
5
Resistors in Series
Presentation to slide 77 +
Problems 33-37
Problems 38-42
6
Resistors in Parallel
Presentation to slide 93 +
Problems 43-44
Problems 45-52
7
Series and Parallel Lamp
Circuit Lab
Lab
Finish lab and prepare for
quiz
8
Series and Parallel Lab
Quiz + Measurement and
Electromotive Force
Quiz & Finish Presentation
+ Problems 53-58
Problems 59-64 &
MC 10-20
9
General Problems
Problems 1, 2, 5, 6
Problems 3, 4, 7
Problems 10, 11, 14, 15
(harder problems can be
left out and replace with
simpler extra practice
problems from the website)
10
General Problems
Problems 8, 9, 12, 13
11
Review MC
Review MC
Study for test
12
Current and Circuits Test
Test
N/A
* It may not be possible to complete labs in the order stated due to lab schedules. Other labs on the
NJCTL website are option and can be used as needed.
**HW Problems are currently not scaffolded from least to most difficult, but are instead listed in order of
topic. Teacher should pay special attention at the end of each class period when assigning HW so that
only problems related to the topic that was taught are being assigned.
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