Chapter 20 Question 63

Static electricity has been studied for a very long time, beginning in 600 BC. People discovered that when amber was rubbed with cat fur, pieces of paper were attracted to the amber. This basic knowledge was able to help later scientists in their studies of static electricity. People experimented with electricity by using conductors, and discovered that sparks, chains, and strips could pass to these conductors which joined the conductors to insulated glass globes (Electrical Machines History). Later, in the seventeenth century, Otto Von Guericke invented a machine that produced static electricity (Artwork LDC). Inside a glass globe, Von Guerbicke placed a sulfur ball mounted on a pole. This machine was rotated by a hand crank. When it was spinning, it rubbed against a pad which then generated static electricity sparks (Artwork LDC). This machine was the first electric generator.
During the eighteenth century, machines involving static electricity improved. One of these machines was the Ramsden Friction Machine. This machine was made up of a circular piece of glass which was on an axle. The machine was turned by a handle which allowed it to rub against two pads. This caused the machine to be electrified on two sides (Electrical Machines History). When the handle turned, the glass plate was charged positively. The plate repelled positive charges to the ends of the conductors and left parts of them with a negative charge (Electrical Machines History). Friction allowed the glass to be continuously positively re-electrified.
In 1772, a scientist by the name of LeRoy invented a machine that included two insulated cyllindric conductors that were placed horizontally. These conductors collected both positive and negative charges. One of the conductors was positively charged while the other was negatively charged (Electrical Machines History). Van Marum created another machine which was similar to Ramsden's. The object of the machine was to collect positive and negative charges (Electrical Machines History).

Works Cited:

Artwork LDC. Ottoman Von Guericke 1602-1686. About.com: Inventors. 2008. 11 March 2008. >.

Electrical Machines History. Sparks Museum Early Radio and Scientific Apparatus. 11 March 2008. <http://www.sparksmuseum.com/FRICTION_HIST.HTM>.

Kodiac1. Static Electricity. Urban Dictionary. 3 July 2006. 11 March 2006. >.