The three most common systems of wiring for general use are ...

[KWilfred]

The three most common systems of wiring for general use are ___________________ _,
  ___________________ _, and ___________________ _.

 
  What will be an ideal response?

Question 2

Explain the principle of magnetism upon which electric motors operate.
 
  What will be an ideal response?

[aadams68]

Answer to Question 1

nonmetallic sheathed cable, armored cable, conduit

Answer to Question 2

A strong magnet is made by wrapping many coils of insulated wire around an iron core and passing
electrical current through the wire. When the current stops flowing, the magnetic field ceases to exist.
If the wires are switched to opposite battery terminals, the poles of the magnet will reverse but the
magnetic field will remain. This unit is called an electromagnet. Bending the electromagnet into the
shape of a horseshoe and suspending a permanent magnet on a bearing between the poles will attract
each other causing the permanent magnet to make a half turn. A device called a commutator causes the
motor to run continuously in the same direction.

[KWilfred]

Thanks for the timely response, appreciate it

[bassamabas]

YES! Correct, THANKS for helping me on my review