What is static electricity?
Static electricity is a buildup of electric charge on the surface of an object. It happens when electrons move from one material to another, often by rubbing, and is released as a spark or shock.
All matter contains positive protons and negative electrons. When two materials touch and separate, such as a balloon rubbed on hair or socks shuffled on a carpet, electrons can jump from one to the other. One object becomes negatively charged and the other positively charged.
Charged objects attract opposite charges and repel like charges. That is why a rubbed balloon sticks to a wall and why hair stands up after taking off a wool hat. When enough charge builds up, it jumps to a nearby conductor, such as a door handle, causing a small spark and shock.
Dry air and lightning
Static shocks are more common in winter, when air is dry. Moist air helps charges leak away. Lightning is a giant form of static discharge, created when charges separate inside storm clouds.
Did You Know?
Static electricity is useful too. Photocopiers and laser printers use it to make toner powder stick to paper, and some air filters use it to trap dust.