Explanation:

The material has no free electron to conduct electric current.

While external forces such as physical rubbing can force some of these electrons to leave their respective atoms and transfer to the atoms of another material, they do not move between atoms within that material cause static electricity.

Examples:

Dry Air, Dry Wood, Rubber, Glass, Plastic, Distilled Water...

Questions:

1. Water conducts electricity. The why water comes under insulators?

2. Air is insulator. Then how we can see lighting in sky?

Related Topics:

1. Insulators.

2. Resistance.

3. Resistors.