What causes the buildup of static electricity, such as when a balloon sticks to hair after rubbing?

Explanation

Static electricity builds up when friction between two surfaces causes electrons to transfer from one material to another, leaving one surface with a slight negative charge and the other slightly positive. This is why rubbing a balloon on hair can make the balloon stick to a wall or cause hair to stand up, as the unlike charges attract each other. The buildup is usually temporary and discharges once the excess electrons find a path to move, sometimes producing a visible spark. Explore more Everyday Science MCQs on mcqstutor to keep practicing.