14.What is the main difference between a generator and an electric motor? A generator produces electricity and an electric motor consumes electricity. A generator uses a permanent magnet and an electric motor uses an electromagnet. A generator produces a magnetic field and an electric motor produces an electric field. A generator uses a rotating magnetic field and an electric motor uses a non-moving magnetic field. 15.A science lab has copper wire coated with rubber tubing, a plastic vial, and a pair of cotton gloves. Which of these materials is not an electrical insulator? A. Copper wire B. Cotton gloves C. Plastic D. Rubber tubing

14) A generator uses a rotating magnetic field and an electric motor uses a non-moving magnetic field.

15) Copper wire

Explanation:

The electric motor is  device that that converts electrical energy into mechanical energy. The armature and coil are positioned between two powerful magnets with a split ring commutator and carbon brushes. A cell is connected to the carbon brushes.

If the armature of the electric motor is made to rotate, it will act as a generator delivering current at the terminals.

An insulator is a material that does not allow electric current to pass through it. Copper allows the passage of electric current hence it is not an insulator.