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Ernest Rutherford was born 30 th August 1871 and died 19 th October 1937. One of the greatest experimental physicists of the 20 th century, Ernest Rutherford was born and grew up in New Zealand. A very bright student, he received a scholarship to Cambridge University, in England in 1895 where he worked under the great English physicist Joseph J. Thomson. In 1898, Rutherford became a physics professor at McGill University in Montreal, Canada. After 9 years at McGill, he became head of physics at Manchester University in England.
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Ernest Rutherford was the son of James Rutherford, a farmer, and his wife Martha Thompson, originally from Hornchurch, Essex, England. James had emigrated from Perth, Scotland, "to raise a little flax and a lot of children". Ernest was born at Spring Grove (now Bright water), near Nelson, New Zealand. His first name was mistakenly spelled Earnest when his birth was registered. He studied at Havelock School and then Nelson College and won a scholarship to study at Canterbury College, University of New Zealand where he was president of the debating society, among other things. After gaining his BA, MA and BSc, and doing two years of research at the forefront of electrical technology, in 1895 Rutherford travelled to England for postgraduate study at the Cavendish Laboratory, University of Cambridge (1895–1898),and he briefly held the world record for the distance over which electromagnetic waves could be detected
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He was knighted in 1914. In 1916 he was awarded the Hector Memorial Medal. In 1919 he returned to the Cavendish as Director. Under him, Nobel Prizes were awarded to Chadwick for discovering the neutron (in 1932), Cockcroft and Walton for an experiment which was to be known as splitting the atom using a particle accelerator, and Appleton for demonstrating the existence of the ionosphere. He was admitted to the Order of Merit in 1925 and raised to the peerage as Baron Rutherford of Nelson, of Cambridge in the County of Cambridge, in 1931, a title that became extinct upon his unexpected death in hospital following an operation for an umbilical hernia (1937). Since he was a peer, British protocol at that time required that he be operated on by a titled doctor, and the delay cost him his life. He is interred in Westminster Abbey, alongside J. J. Thomson, and near Sir Isaac Newton.
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During the investigation of radioactivity he coined the terms alpha and beta in 1899 to describe the two distinct types of radiation emitted by thorium and uranium. These rays were differentiated on the basis of penetrating power. From 1900 to 1903 he was joined at McGill by the young Frederick Soddy (Nobel Prize in Chemistry, 1921) and they collaborated on research into the transmutation of elements. Rutherford had demonstrated that radioactivity was the spontaneous disintegration of atoms. He noticed that a sample of radioactive material invariably took the same amount of time for half the sample to decay—its "half-life"— and created a practical application using this constant rate of decay as a clock, which could then be used to help determine the age of the Earth, which turned out to be much older than most of the scientists at the time believed.
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In Manchester he continued to work with alpha radiation, in conjunction with Hans Geiger he developed zinc sulphide scintillation screens and ionization chambers to count alphas. By dividing the total charge they produced by the number counted, Rutherford decided that the charge on the alpha was two. In late 1907 Rutherford Thomas Royds allowed alphas to penetrate a very thin window into an evacuated tube. As they sparked the tube into discharge, the spectrum obtained from it changed, as the alphas were trapped. Eventually, the clear spectrum of helium gas appeared, proving that alphas were at least ionized helium atoms, and probably helium nuclei. Along with Hans Geiger and Ernest Marsden he carried out the Geiger– Marsden experiment in 1909, which demonstrated the nuclear nature of atoms.
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