2.20 describe experiments to investigate how insulating materials can be charged by friction

Static Electricity

Take a rod of plastic such as acetate or polythene and rub a cloth duster against them. This builds up static charge. Then take a positively charged material and tie it to a string so its suspended at the halfway line. Take the plastic rod and place it near to this material. If the rod is positive it will repel and if it's negative then it will attract.