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Potential and Field. Connection between Potential and Fields Electric Field around a Conductor EMF or Batteries. Reading Questions. What quantity is represented by the symbol ?. 1. Electronic potential 2. Excitation potential 3. Electromotive force 4. Electric stopping power
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Potential and Field Connection between Potential and Fields Electric Field around a Conductor EMF or Batteries
Reading Questions What quantity is represented by the symbol ? 1. Electronic potential 2. Excitation potential 3. Electromotive force 4. Electric stopping power 5. Exosphericity
Reading Questions What quantity is represented by the symbol ? 1. Electronic potential 2. Excitation potential 3. Electromotive force 4. Electric stopping power 5. Exosphericity
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.
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.
Reading Questions The relationship ∆V=IR is called 1. Faraday’s law. 2. Ampere’s law. 3. Ohm’s law. 4. Maxwell’s equation. 5. No name was given in this chapter.
Reading Questions The relationship ∆V=IR is called 1. Faraday’s law. 2. Ampere’s law. 3. Ohm’s law. 4. Maxwell’s equation. 5. No name was given in this chapter.
Energy concept Electric Field and Potential Force concept Acts locally Everywhere in space
Hand waving argument using a constant electric field Connecting Potential and Field Recall from the last lecture we found From Calculus III we find
Energy concept Electric Field and Potential Force concept Acts locally Everywhere in space
TACTICS BOX 30.1 ‑Finding the potential difference from the electric field • 1) Draw a picture and identify the two points between which you wish to find the potential. Call them positions i and f. • If you need to assign a specific value of V to a point in space, choose position f to be the zero point of the potential, usually at infinity. • Establish a coordinate axis from i to f along which you already know or can easily determine the electric field component • 4) Carry out the integral of Equation 30.3 to find the potential difference Potential from Electric Field Calculating the potential from the electric field.
Or for one dimension Electric Field from Potential Recall
Electric Field and Potential Kirchhoff’s Loop Law The sum of the voltages aroung a closed path equal zero.
Student Workbook You should do this one.
Vector so - - Student Workbook You should do this one.
Class Question Which potential-energy graph describes this electric field? 1. a 2. b 3. c 4. d 5. e
Class Question Which potential-energy graph describes this electric field? 1. a 2. b 3. c 4. d 5. e
Which set of equipotential surfaces matches this electric field? (1) (2) (3) (5) (4) Class Question
Which set of equipotential surfaces matches this electric field? (1) (2) (3) (5) (4) Class Question
Gaussian surface Electric Field around Conductors + +
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 > E2 > E3 3. V1 > V2 > V3 and E1 = E2 = E3 4. V1 > V2 > V3 and E1 > E2 > E3 5. V3 > V2 > V1 and E1 = E2 = E3
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 > E2 > E3 3. V1 > V2 > V3 and E1 = E2 = E3 4. V1 > V2 > V3 and E1 > E2 > E3 5. V3 > V2 > V1 and E1 = E2 = E3
Student Workbook You should do this one.
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 >Ic =Id 3.Ic =Id >Ia =Ib 4. Ic =Id >Ia >Ib 5. Ia >Ib >Ic =Id
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 >Ic =Id 3.Ic =Id >Ia =Ib 4. Ic =Id >Ia >Ib 5. Ia >Ib >Ic =Id