Reading:

Cutnell and Johnson, Chapter 22 (excluding section 22.6).

Problems for Review:

Reviewing these problems gives you good exposure to this week's main topics, in practice. All are worked in the Student Study Guide [SSG] or Student Solutions Manual [SSM]; solutions are posted on our website http://www.physics.emory.edu/Classes/142-003.html , for those without these texts.

Conceptual:

MCAT review problem, [SSG] p 434.

Quantitative:

Chapter 22, problems 5,9,13,17,21,33,37,65,73,77.

Problems to Hand In:

Conceptual:

Use the following to answer questions 1--6:

Two coils, 1 and 2, with iron cores are positioned as shown below. Coil 1 is part of a circuit with a DC battery and switch. Iron has magnetic permeability .

1. Say coil 1 is 10 cm long and has 240 turns. What magnetic field is induced at the center of coil 1 when the current in circuit 1 is 2 A?
   1. 3.3 T, toward A
   2. 3.3 T, toward B
   3. 33 T, toward A
   4. T, toward A
   5. T, toward B
2. The circuit containing coil 1 is altered. Which one of the following is a consistent response by circuit 2?
   1. An induced current flows left to right through resistor R, with an induced toward C and an induced north magnetic pole at the right end of coil 2.
   2. An induced current flows left to right through resistor R, with an induced toward B and an induced north magnetic pole at the left end of coil 2.
   3. An induced current flows left to right through resistor R, with an induced toward B and an induced north magnetic pole at the right end of coil 2.
   4. An induced current flows right to left through resistor R, with an induced toward B and an induced north magnetic pole at the left end of coil 2.
   5. An induced current flows right to left through resistor R, with an induced toward C and an induced north magnetic pole at the left end of coil 2.
3. Assume the switch S has been closed for a long time. Which one of the following statements is true?
   1. An induced current will flow from right to left in R.
   2. An induced current will flow from left to right in r.
   3. A magnetic field that points toward B appears inside coil 1.
   4. An induced magnetic field that points toward B appears inside coil 2.
   5. A current will pass through r, but there will be no current through R.
4. Assume S has been closed for a long time. Which one of the following statements is true when coil 1 and its core are moved toward point B?
   1. There is no induced current in r.
   2. There is a magnetic field in coil 1 that points toward B.
   3. There is an induced current in R that flows from left to right.
   4. There is an induced current in R that flows from right to left.
   5. There is an induced magnetic field in coil 2 that points toward B.
5. Assume S has been closed for a long time. Which one of the following statements is true when coil 2 and its core are moved toward point C?
   1. There is an induced magnetic field in coil 2 that points toward B.
   2. There is an induced magnetic field in coil 2 that points toward C..
   3. There is an induced current in R that flows from right to left.
   4. There is an induced north pole at the right end of coil 2.
   5. There is no induced current in R.
6. Assume S has been closed for a long time. Which one of the following changes will result in an induced magnetic field in coil 2 that points toward C?
   1. The switch S is opened.
   2. The iron core is removed from coil 1.
   3. Coil 1 and its core are moved toward A.
   4. Coil 1 and its core are moved toward B.
   5. Coil 2 and its core are moved toward C.

Quantitative:

Chapter 22, problems 14, 16, 22, 30, 50, 64, 67, 76.

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