Insulators are materials that

• A. Resist electrical conduction
• B. Store magnetic energy
• C. Conduct electricity easily
• D. Increase current flow

Answer: (A)

Insulators are materials that resist electrical conduction. They have high resistance and little free movement of charge carriers, so electric current does not pass through easily. This property makes them ideal for keeping electricity contained and preventing shocks, as seen in rubber or plastic insulation on wires and ceramic insulators on utility poles and equipment. They also possess good dielectric strength, meaning they can withstand high voltages without breaking down. They do not store magnetic energy; that’s a property of magnetic materials. And they do not act to increase current flow; in fact, they are used to inhibit current from flowing where it shouldn’t.