What term describes a material that does not transmit electricity?

• A. Conductor
• B. Nonconductor
• C. Insulator
• D. Metal

Answer: (B)

Materials that block electrical flow are insulators. An insulator has high electrical resistance, so electrons aren’t free to move and current doesn’t pass through easily. This is why substances like rubber, glass, and plastic are used to coat or separate conductors to keep electricity from escaping where it shouldn’t. Metals and other conductors, by contrast, let current flow readily, which is the opposite behavior described here. While you might hear “nonconductor” in everyday language, the precise term in electrical contexts is insulator, because it clearly denotes a material that resists conduction.