Question

which of the following is a good insulator of electricity?
a salt water
b rubber
c iron
d copper

Explanation:

To determine a good electrical insulator, we analyze each option:

• Option a: Salt water contains ions, making it a conductor.
• Option b: Rubber is a non - metal and does not allow electric current to flow easily, so it is an insulator.
• Option c: Iron is a metal and a good conductor of electricity.
• Option d: Copper is also a metal and a well - known conductor.

Answer:

b. Rubber