Magnetic Effects of Electric Current

Topics in this chapter

• Magnetic Fields from Current
• Magnetic Force on Conductors
• Electric Motor Principles
• Electromagnetic Induction and Generators
• Domestic Circuits and Power
• Electrical Safety and Protection

Cheat sheet

Practice questions

1. Question 1Q-6DC7DD

   Which of the following correctly describes the magnetic field inside a long straight solenoid carrying-current?

   1. A.The magnetic field is zero.
   2. B.The magnetic field is uniform and represented by parallel straight lines.
   3. C.The magnetic field is strongest near the ends and weakest at the center.
   4. D.The magnetic field changes continuously in magnitude from point to point.
   See the answer and solution
2. Question 2Q-C916F0

   State the rule used to determine the direction of the magnetic field produced around a current-carrying straight conductor. Name the rule and state its direction.

   See the answer and solution
3. Question 3Q-B4A2B5

   The phenomenon of electromagnetic induction is:

   1. A.the process of charging a body.
   2. B.producing induced current in a coil due to relative motion between a magnet and the coil.
   3. C.the force acting on a current-carrying conductor in a magnetic field.
   4. D.the production of a magnetic field by a current-carrying wire.
   See the answer and solution
4. Question 4Q-149D20

   An electron enters a uniform magnetic field at right angles to it, as shown in a hypothetical setup. The direction of force acting on the electron will be:

   1. A.to the right
   2. B.to the left
   3. C.into the page / opposite to Fleming's Left-Hand Rule direction for conventional current
   4. D.parallel to the magnetic field
   See the answer and solution
5. Question 5Q-B2B841

   Explain why two magnetic field lines never intersect each other.

   See the answer and solution