Chapter 20 Question 63

Leyden Jar
It is a devide for storing electrical charge and was invented in 1745 Pieter van Musschenbroek. It was the first capacitor and was used to conduct experients dealing with electricity. the design consists of an electrode connected to a metal foil folding part on the inner surface of a glass jar. The conducting foil is wrapped around the outside of the jar which is charged by an electrostatis generator, which is connected to the inner electrode and the outter plate is grounded. Both the inner and outter surfaces of the jar hold opposite charges. Originally it was a glass bottle partially filled with water with a wire passing through the cork that closed it. Benjamin Frankilin found out the charge was stored in the glass and not the water.
Franklin's Bells
During one of his initial experiments he noticed that a pith ball or cork would be repelled if touched together but initially would be attracted to a charged object. he realized this because the two objects were initially charged differently, but once they touched they acquired the same charge. He later realized if he replaced the charged object with a bell he could make an "electric bell." Later he used the bell as a lightning detector. When the bell was connected to a lightning rod it would ring when an electrical storm was nearby.