Electrifying a Bubble

The bubbles for this experiment have a longer life than those usually obtained from ordinary soap solution. The addition of glycerin to soapy water should provide a mixture that will prove ideal for the purpose. If you are unable to get a bubble-pipe, a loop of wire will serve as well.

Take a length of fairly thick wire (hairpin thickness) and bend it into the loop shape shown in the diagram.

Dip the wire loop into the soap and glycerin solution so that a film of liquid forms across the wire when it is removed.

Either blow gently into this film or else give the wire a sharp flick in the air to form bubbles.

When you are satisfied with the bubbles you can produce, switch to a second operation: Rub an old phonograph record with a piece of fur or flannel. This is best done in a warm, dry room. Rub the record briskly for a minute or two.

Now, without any loss of time, blow a bubble, catch it on a piece of paper, and then gently roll it onto the phonograph record. A friend can help by blowing a bubble while you are rubbing the record.

Allow the bubble to rest on the record for a few seconds and then gently shake the bubble free. As it falls, lower the record so that it is immediately below the bubble. As the bubble nears the record it will slow in speed until it hovers over it. By careful manipulation of the record, you can keep the bubble in this hovering position either until it bursts or until some wayward current of air blows it aside.

In rubbing the phonograph record you produced an electrical charge which was imparted to the bubble when it rested on the record. As both the record and the bubble were in this way given like charges of electricity, they began to repel each other when the bubble was shaken off.