In 1872, Russian Alexander Lodygin invented an incandescent light bulb and obtained a Russian patent in 1874. He used as a burner two carbon rods of diminished section in a glass receiver, hermetically sealed, and filled with nitrogen, electrically arranged so that the current could be passed to the second carbon when the first had been consumed. Later he lived in the USA, changed his name to Alexander de Lodyguine and applied and obtained patents for incandescent lamps having chromium, iridium, rhodium, ruthenium, osmium, molybdenum and tungsten filaments, and a bulb using a molybdenum filament was demonstrated at the world fair of 1900 in Paris. COUNT 5
QSN1 Who patented an incandescent light bulb in Russia in 1874? ANS1 Alexander Lodygin QSN2 What did Lodygin use as a burner in his lamp? ANS2 two carbon rods QSN3 In what year did Lodygin demonstrate a lamp at the World's Fair? ANS3 1900 QSN4 What did Lodygin change his name to after moving to the USA? ANS4 Alexander de Lodyguine QSN5 When did Lodygin invent his first lamp? ANS5 1872