Download 09 Physics II Final Exam Term 1 Study Guide File

Physics II, Dr. Fisher
Term 1 – Final Exam Study Guide
Exam date: 21 November 2014
This Study Guide is given as a reminder of concepts and terms that were identified and/or covered in class and that I will
hold you accountable for. This list is a reference only. For details, you should rely on our class discussions, the text
readings (note, a few concepts we discussed in class but are not in the text), and the homework problems .
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For this exam, a calculator will be necessary, and it should do trig functions.
I will provide some equations, shown on the last page of this handout.
Be prepared to define terms that we have used repeatedly.
Be prepared to solve problems in the method I have instructed. I will grade your setup and symbolic solution as
well as the numeric solution. So please, show sketches, and show solutions in symbolic form.
Some questions will require symbolic solutions, and some will require numeric solutions where significant
figures and units need to be managed.
Terms and concepts to know, understand, and apply. (for each chapter, I’ve highlighted some key concepts that deserve
particular attention by this class.
FOLLOW THE CHARGE………………………….UNDERSTAND THE CHARGE…………………THINK LIKE THE CHARGE…………
The exam covers
Chapter 16, sections 1-9. It also covers parts of chapter 5 section 6 for analogy to Coulomb’s law.
The material we’ve covered is both quantitative and conceptual. You need to have an understanding of:
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how static charge behaves
the electroscope behavior
Coulomb’s law
Newton’s law of universal gravitation
Definitions and understanding of charge, insulator, conductor, induced charge
Electric field and analogy to gravity field
Field lines, their definition and how to draw for 6-10 geometries
o Like point charges, 2 unlike point charges, uneven point charges
o Infinite plane and point charge
o In a conductor and around a conductor
Lightning: how it is created, especially field lines
The in-class minilab on charge dissipation—concepts and findings
The physlets on static charge behavior that I discussed in class
Chapter 17, sections 1-5, 7-10.
Electric potential is the most difficult concept to master, so far.
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Relation of work, the work of moving a charge, to potential energy.
o Be sure you understand fully the signs of these relationships
Potential, V, as the potential energy per charge V = PE/q
o Check the units of Volts to make this more understandable
Physics II Term 1 Final Exam study guide
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The analogy to PEg, the gravitational potential energy
If you have potential, you can find Electric field V=-Ed
o Why is the negative sign there? The change in electric potential is the negative of the work done BY
the electric force. And the work done by the force is W = qEd
a point charge creates an electric field, and it thus has an electric potential caused by it.
We can store charge (capacitor); know how it works, understand the charges on it.
Dielectics affect capacitance: how?
Since they store charge (at a potential difference), they also store energy. PE = U = ½ QV
Know how a CRT works. (cathode ray tube)
Chapter 18, sections 1-6 and part of 7.
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We looked at batteries qualitatively, not many details.
Current is charge on the move: why does it move? It is conserved? How to define and calculate?
Ohm’s law is hugely important, and simple.
What is a resistor doing physically to the moving electrons to give resistance to flow?
Know how the resistance changes with temperature for conductors
How does electrical power differ from mechanical power? How are they the same?
o Calculate electrical power
o Know how to decide what is being held constant for a given power problem: I or V.
How to relate power to energy: E = P t
Know the basic definition of AC. Does AC have +/- polarity in the circuit?
Power problems were the most important problem of chapter 18
Chapter 19, sections 1-5
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We’re still following the charge, and this time it is running around the loop of wire, driven by what?
o Does the same electron go around the circuit multiple times?
Define EMF to distinguish the ideal potential of the source from the actual potential Vab.
o Know the Vab equation.
We learned a few rules to characterize the series and parallel resistors. These are derived based on two
fundamental and important concepts
o Current (charge) is conserved, and therefore constant through a given loop or circuit
o Voltage potential is same at all points on a (ideal) conductor, and thus the voltage drop across any
parallel elements is the same
So for simple circuits you can reduce them to Req and then back out the various voltage drops and currents
o Know what a voltage drop is and how to calculate it.
For more complex circuits, you learned Kirchhoff’s rules
o Current is conserved, so I can conserve current at any node in a circuit
o Potential Energy is conserved, so the sum of potentials around a loop is always zero.
And of course you have to apply the Kirchhoff rules to many problems
o First get all the currents, then back out to get any voltages or power you need
In section 19-4, we learned only that batteries add up, but didn’t do anything with battery charging.
Physics II Term 1 Final Exam study guide
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Labs and concepts from them:
Of course you are responsible for the lab concepts, so review
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How an electroscope works
What a Faraday cage can do
How the parallel plate capacitor behaves as you charge and discharge it
Ohms law applied to a variety of conductors, and how you measured and calculated R
Equations and information that will be given on the final.
Physics II, Term 1
constants
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k = 9.0 x 109 N.m2/C2
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G = 6.67 x 10-11 N.m2/kg2
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0 = 1/(4k) = 8.85x10-12 C2/N.m2
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 for copper = 1.68 x 10-8  m
equations
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F = k Q1Q2/r2
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E = F/q
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W = F . d = PE for conservative force
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V = W/q = E . d
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V = kQ/r
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For pp capacitor
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Q=CV
U = ½ Q2/C = ½ QV
C = 0A/D
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PE = qV
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T = o[1 +  (T-To)]
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V = E – Ir
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R =  L/A
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I’ll give you kinematic equations if you need them.
Physics II Term 1 Final Exam study guide
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