An insulator is any material in which electric current does not flow freely. Examples include rubber, glass, plastic, and ceramic..

A conductor is any material that allows electricity and heat to flow through freely. The best conductors are certain metals, such as silver and copper.

Think about common items in your home or classroom. Identify at least two items that are insulators and one item that is a conductor.

Imagine one tiny particle bumps another, and that bumps another, and it keeps going. What do you think might happen if this happens millions of times each second?

List three forces you can’t see but know are real. How do you know they’re real?