Potential and Field

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Potential and Field

• Connection between Potential and Fields
• Electric Field around a Conductor
• EMF or Batteries

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Reading Questions
What quantity is represented by the symbol ?
1. Electronic potential 2. Excitation
potential 3. Electromotive force 4. Electric
stopping power 5. Exosphericity
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Reading Questions
What quantity is represented by the symbol ?
1. Electronic potential 2. Excitation
potential 3. Electromotive force 4. Electric
stopping power 5. Exosphericity
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Reading Questions
The electric field
1. is always perpendicular to an equipotential
surface. 2. is always tangent to an equipotential
surface. 3. always bisects an equipotential
surface. 4. makes an angle to an equipotential
surface that depends on the amount of charge.
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Reading Questions
The electric field
1. is always perpendicular to an equipotential
surface. 2. is always tangent to an equipotential
surface. 3. always bisects an equipotential
surface. 4. makes an angle to an equipotential
surface that depends on the amount of charge.
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Reading Questions
The relationship ?VIR is called
1. Faradays law. 2. Amperes law. 3. Ohms
law. 4. Maxwells equation. 5. No name was given
in this chapter.
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Reading Questions
The relationship ?VIR is called
1. Faradays law. 2. Amperes law. 3. Ohms
law. 4. Maxwells equation. 5. No name was given
in this chapter.
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Electric Field and Potential
Force concept
Acts locally
Everywhere in space
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Connecting Potential and Field
Recall from the last lecture we found
From Calculus III we find
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Electric Field and Potential
Force concept
Acts locally
Everywhere in space
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Potential from Electric Field
Calculating the potential from the electric field.

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Electric Field from Potential
Recall
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Electric Field and Potential
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Electric Field from Potential
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Electric Field and Potential
Kirchhoffs Loop Law
The sum of the voltages aroung a closed path
equal zero.
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Student Workbook
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Student Workbook
You should do this one.
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Student Workbook
You should do this one.
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Student Workbook
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Student Workbook
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Student Workbook
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Student Workbook
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Class Question
Which potential-energy graph describes this
electric field?
1. a 2. b 3. c 4. d 5. e
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Class Question
Which potential-energy graph describes this
electric field?
1. a 2. b 3. c 4. d 5. e
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Class Question
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Class Question
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Electric Field around Conductors


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Electric Field and Potential
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Electric Field and Potential
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Student Workbook
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Student Workbook
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Student Workbook
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Class Question
Three charged, metal spheres of different radii
are connected by a thin metal wire. The potential
and electric field at the surface of each sphere
are V and E. Which of the following is true?
1. V1 V2 V3 and E1 E2 E3 2. V1 V2
V3 and E1 gt E2 gt E3 3. V1 gt V2 gt V3 and E1 E2
E3 4. V1 gt V2 gt V3 and E1 gt E2 gt E3 5. V3 gt
V2 gt V1 and E1 E2 E3
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Class Question
Three charged, metal spheres of different radii
are connected by a thin metal wire. The potential
and electric field at the surface of each sphere
are V and E. Which of the following is true?
1. V1 V2 V3 and E1 E2 E3 2. V1 V2
V3 and E1 gt E2 gt E3 3. V1 gt V2 gt V3 and E1 E2
E3 4. V1 gt V2 gt V3 and E1 gt E2 gt E3 5. V3 gt
V2 gt V1 and E1 E2 E3
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EMF or Battery
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EMF or Battery
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Student Workbook
You should do this one.
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Student Workbook
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Class Question
A wire connects the positive and negative
terminals of a battery. Two identical wires
connect the positive and negative terminals of an
identical battery. Rank in order, from largest to
smallest, the currents Ia to Id at points a to d.
1. Ia Ib Ic Id 2. Ia Ib gt Ic Id 3.
Ic Id gt Ia Ib 4. Ic Id gt Ia gt Ib 5. Ia
gt Ib gt Ic Id
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Class Question
A wire connects the positive and negative
terminals of a battery. Two identical wires
connect the positive and negative terminals of an
identical battery. Rank in order, from largest to
smallest, the currents Ia to Id at points a to d.
1. Ia Ib Ic Id 2. Ia Ib gt Ic Id 3.
Ic Id gt Ia Ib 4. Ic Id gt Ia gt Ib 5. Ia
gt Ib gt Ic Id