THE ELECTROPHORUS

Some credit Alessandro Volta with its invention in 1775, but According to most sources, the electrophorus was invented in 1762 by Swedish physicist Johan Carl Wilcke, who was the son of a German pastor in Stockholm. Some credit Alessandro Volta with its invention in 1775, but most agree that he simply improved Wilcke’s earlier invention. Volta is, however, credited with naming Wilcke’s electrostatic generator the electrophorus, meaning “electricity bearer” in Greek. See the following web sites for more information http://www.magnet.fsu.edu/education/tutorials/museum/electrophorus.html http://en.wikipedia.org/wiki/Electrophorus

According to Wikipedia and other sources, one of the largest examples of an electrophorus was built in 1777 by German scientist Georg Christoph Lichtenberg, who was the son of a Lutheran pastor. It was 6 feet (2 m) in diameter, with the metal plate raised and lowered using a pulley system. It could reportedly produce 15 inch (38 cm) sparks. Lichtenberg used its discharges to create the strange treelike marks which became known as Lichtenberg figures.

Rub the foam board with the fur. While touching only the foam cup, place the metal pie pan on the board. Touch the rim of the pie pan. Pick the pan up and touch it again. Do this again, but touch it with the light bulb.

Rub the foam board with the fur. While touching only the foam cup, place the metal pie pan on the board. Hold a finger near the foil ball. Observe what happens! Pick the pan up and once again hold your finger near the foil ball. Observe what happens!

A positively charged piece of Styrofoam is placed on the table. A neutral aluminum pie plate is brought near as shown below. While held above the Styrofoam, the aluminum plate is touched (grounded).                                                                                                                                                                               At this point, there is a movement of electrons. Electrons move ____ . a. out of the aluminum plate into the ground (hand) b. into the aluminum plate from the ground (hand) c. into the aluminum plate from the Styrofoam d. out of the aluminum plate into the Styrofoam e. from the ground through the aluminum plate to the Styrofoam f. from the Styrofoam through the aluminum plate to the ground g. .... nonsense! Electrons do not move at all.