Which of the following is a good electrical insulator?

Which of the following is a good electrical insulator?

• A. Copper
• B. Glass
• C. Aluminum
• D. Mercury

Answer: (B)

Glass is an excellent electrical insulator because it has a very high resistance to electric current. Unlike metals such as copper and aluminum, which are conductive and allow electrons to flow easily, glass does not conduct electricity under normal conditions. This property makes glass useful in electrical applications where insulation is necessary to prevent unwanted current flow, such as in capacitors or as supports for wires. In contrast, copper and aluminum are good conductors and are commonly used in electrical wiring and circuits. Mercury, while a metal, is somewhat conductive as well, making it unsuitable for applications where insulation is required. Therefore, glass stands out as the best choice among the options provided for its ability to effectively insulate against electrical current.

Glass is an excellent electrical insulator because it has a very high resistance to electric current. Unlike metals such as copper and aluminum, which are conductive and allow electrons to flow easily, glass does not conduct electricity under normal conditions. This property makes glass useful in electrical applications where insulation is necessary to prevent unwanted current flow, such as in capacitors or as supports for wires.

In contrast, copper and aluminum are good conductors and are commonly used in electrical wiring and circuits. Mercury, while a metal, is somewhat conductive as well, making it unsuitable for applications where insulation is required. Therefore, glass stands out as the best choice among the options provided for its ability to effectively insulate against electrical current.