Pocket Genius Science: Energy and forces – Electricity

Facts At Your Fingertips: Energy and forces – Electricity

All atoms contain positively charged protons and negatively charged electrons. Electricity is a flow of charged electrons from one place to another.

When electrons are transferred between substances, it can cause a buildup of negative charge in one place and positive charge in another— sometimes with powerful results.


Inside storm clouds tiny particles of ice rub against each other and electrons are transferred between particles.

This leads to a buildup of negative charge at the bottom of the cloud. If this charge becomes large enough, it can jump between clouds or a cloud and the ground in a massive bolt of electricity, known as lightning.

Static electricity

When electrical charge builds up in one place it is called static electricity. If you rub your hair on a balloon, electrons are transferred from your hair to the balloon. This gives your hair a positive charge and the balloon a negative charge.

Particles with opposite charge are attracted to each other so your hair will stick to the balloon.

Current electricity

The electricity that powers our homes is known as current electricity.

It flows from power plants to our homes and offices along long electric cables that are made from conducting materials. These cables are supported by towers that are protected from the current by ceramic insulators.