Also known as an insulator, this material prevents the flow of electricity.

Also known as an insulator, this material prevents the flow of electricity.

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

Answer: (B)

The main idea here is that some materials block the flow of electric current. Materials that block current are called insulators, or nonconductors. They have high resistivity and few free charges that can move, so electricity doesn’t pass through easily. That’s why a nonconductor is described as an insulator. Metals and other conductors, by contrast, have many free electrons that move readily, so they allow current to flow. A conductor is simply something that conducts electricity. Volt isn’t a material at all—it's a unit of electrical potential, not a substance. So the best fit for “also known as an insulator, this material prevents the flow of electricity” is nonconductor.

The main idea here is that some materials block the flow of electric current. Materials that block current are called insulators, or nonconductors. They have high resistivity and few free charges that can move, so electricity doesn’t pass through easily. That’s why a nonconductor is described as an insulator.

Metals and other conductors, by contrast, have many free electrons that move readily, so they allow current to flow. A conductor is simply something that conducts electricity. Volt isn’t a material at all—it's a unit of electrical potential, not a substance.

So the best fit for “also known as an insulator, this material prevents the flow of electricity” is nonconductor.