A Comb That Picks Up Paper
- Rub a plastic comb in dry hair, then hold it over torn paper
- The pieces jump upwards before the comb even touches them
- Take off a woollen jumper in the dark: crackling and tiny sparks
- Both are the same thing. Both are static electricity
Presenter notes: Do the trick before you say a single word. Tear a page into tiny pieces on the front desk, run a plastic comb through your hair twenty times, and hold it above them. They will jump. Then ask the question that runs the whole period: where did that electricity come from? Somebody will say you made it by rubbing. Push back gently. If rubbing makes electricity, then rubbing anything should make it, and by the end of the period they will have watched a steel spoon rubbed just as hard do absolutely nothing. Tell them the answer is stranger and simpler than making electricity: nothing was made at all.