B. Materials that do not let electricity flow through them are called insulators. Most conductors are insulated with material that does not allow electricity to flow through it. Rubber and plastic are insulators used to cover wires so electricity does not leak out. When an electric current is run through a conductor, many useful effects are produced. An electric current can produce heat.
Heat is produced when an electric current is pushed through a poor conductor.
A poor conductor will make the electrons work harder than normal to move through the wires. Poor conductors will resist the flow of electrons. This is called resistance. B. An electric current can produce light. When an electric current flows through a filament, a thin piece of wire that resists the flow of electricity, it creates electric heat.