Obedient pole

We need: a piece of fabric, a pole, a glass, a piece of cork, a needle, a bottle

I put a needle into a piece of cork. The sharp end of the needle is outside of the cork. I put the cork in a neck of a bootle. I put a glass on the needle. I charge a pole by rubbing with a piece of fabric. I put the pole on the glass. I put my thumb close to the pole and make it move.