What is happening?
Need: a candle or glass rod old phonograph record (vinylite LP or shellac) Piece of flannel or wool Unpainted metal disk, like a jar topHeat the flat end of the candle and use the wax to attach the candle to the center of the metal disk. Or glue the glass rod to the center of the disk. This will serve as the insulating handle so that you can carry the charged disk without releasing the charge.
With the flannel or wool, rub the record vigorously for 30 seconds over an area large enough for the metal disk.
Holding by the candle, place the metal disk over the charged area. For a second, touch the disk with a finger of the other hand. Lift the disk byt the handle. The disk is now positively charged. Bring it close to your other hand and you will get a slight shock.
You can touch the disk to the record several times and still get a charge and this can now be used to charge your Leyden Jar
What is happening?
1. Rubbing the record surface gave it a negative charge
2. Placing the disk on the record forced the negative electons away from the record to the topside of the disk
3. Touching the disk with fing alows the electrons move away to ground (you are grounded)
4. The removed disk now has less electrons than protons so it is positively charged.