Question 63

The leyden jar was used by early experimenters to store electricity. The leyden jar consisted of an insulator with a layer of metal on the inside and the outside of it. The inside metal is given a charge with the outside metal being grounded. When this occurs the outside metal has an equal but opposite reaction. When the outside and inside metals are connected a spark occurs and both metals are grounded. Scientists today would call a machine like this a capacitator. In Wimshurst design, the disks contra-rotate. The metal foil sectors on the disks induce charges on each other, which are picked off with metal brushes and stored in Leiden jars. The machine was developed to form high voltages in the late 19th century. The positive feedback of the Wimshurst design increases the accumulating charges until the breakdown voltage of the air is reached and a spark jumps across the gap. Both of these designs were very successful during their time in studying static electricity.