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Reading Quiz Number 11

Question 1: "Induced EMF" is a voltage created by

  1. a solenoid
  2. a changing electric field
  3. a changing magnetic field
  4. currents through long, straight wires 
  Answer: C, a changing magnetic field

Question 2: The magnetic field in this room runs roughly from North to South -- that is, from the front of the room to the back. An iron ball is dropped from the ceiling. As it falls to the floor, a voltage is induced within it which is

  1. positive at the top, negative at the bottom
  2. positive at the Eastern edge, negative at the Western edge
  3. positive at the Northern edge, negative at the Southern edge
  4. positive at the Western edge, negative at the Eastern edge 
      Answer: D.  The induced voltage is positive on the Western edge,
                 negative on the Eastern edge

    Question 3: What are the SI units of magnetic flux? 

      Answer: magnetic flux   =  (magnetic field) * (area)
  
                          =  (    Tesla     ) * (square meters)

          which is also called "Webers", or "Wb" for short

    Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.