Presentation on theme: "Stephen Gray (December 1666 – 7 February 1736)"— Presentation transcript:
1 Stephen Gray (December 1666 – 7 February 1736) He was an English dyer and amateur astronomer, who was the first to systematically experiment with electrical conduction, rather than simple generation of static charges and investigations of the static phenomena.
2 Discovery of Stephen Gray Stephen Gray was pursuing a long series of experiments with electricity. In producing charge on a long glass tube, he discovered in 1729 that he could communicate the electrical effect to other objects by direct connection.Using string, he could charge an object over 50 feet from the rubbed tube, but oddly enough some other substances, such as silk thread, would not carry charge. Brass wire would transmit charge even better. These experiments with charged strings and glass tubes revealed the properties of conduction, insulation, and transmission.
3 Discovery of Stephen Gray Gray's conduction experimentIn a famous experiment Stephen Gray demonstrated static electricity by charging a boy suspended by insulating strings in 1744
4 The Flying BoyThe Flying Boy was perhaps the most famous and celebrated demonstration of its time. People all over Europe wrote about it, and imitated it.The Royal Society of London awarded Gray the first Copley Medal, "for his new Electrical Experiments - as an encouragement to him for the readiness he has always shown in obliging the Society with his discoveries and improvements in this part of Natural Knowledge."
5 Jean Dufay (July 18, 1896–November 6, 1967) He was a French astronomer. During his career he studied nebulae, interstellar matter, the night sky and cometary physics. He became a member of the French Academy of Sciences in 1963.His undergrad was completed in 1913 and his Ph.D. in 1928 under Charles Fabry. In between he served (and was wounded) in World War I and taught.The crater Dufay on the Moon is named after him.
6 Luigi Aloisio Galvani (September 9, 1737 – December 4, 1798) He was an Italian physician, physicist and philosopher who lived and died in Bologna. In 1780, he discovered that the muscles of dead frogs legs twitched when struck by an electrical spark.This was one of the first forays into the study of bioelectricity, a field that still studies the electrical patterns and signals of the nervous system.
7 Luigi Aloisio Galvani (September 9, 1737 – December 4, 1798)
8 Galvani's experiment on frog legs Electrodes touch a frog, and the legs twitch into the upward position
9 Alessandro Volta (February 18, 1745 – March 5, 1827) Alessandro Volta was a physicist, chemist and a pioneer of electrical science.He invented in 1800 the first electrical battery – which people called the “voltaic pile.”With this invention, scientists could produce steady flows of electric current, unleashing a wave of new discoveries and technologies.
10 A voltaic pile on display in the museum near Volta's home in Como The voltaic pile was the first electrical battery that could continuously provide an electrical current to a circuit.It was invented by Alessandro Volta, who published his experiments in 1800A voltaic pile on display in the museum near Volta's home in Como
11 Alessandro Volta (February 18, 1745 – March 5, 1827)