Edward Victor Appleton

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Edward Victor Appleton bigraphy, stories - English physicist

Edward Victor Appleton : biography

6 September 1892 – 21 April 1965

Sir Edward Victor Appleton, GBE, KCB, FRS (6 September 1892 – 21 April 1965) was an English physicist.

Legacy

  • the Rutherford Appleton Laboratory
  • the Appleton Tower at the University of Edinburgh
  • the at Bradford College
  • Appleton Academy, an up and coming new school, which will replace Wyke Manor School and High Fernley Primary School in the Wyke district of South Bradford. This will be the first ‘through-school’ in West Yorkshire.
  • The crater Appleton on the Moon is named in his honour.
  • The Appleton Layer, which is the higher atmospheric ionized layer above the E-layer
  • The annual at the , IET.
  • Likely inspiration for the pseudonym Victor Appleton – the fictitious author of the Tom Swift series of novels
  • Appleton Academy in Bradford Wyke

Biography

Appleton was born in Bradford, West Yorkshire and educated at Hanson Grammar School. At the age of 18 he won a scholarship to St John’s College, Cambridge. He graduated with a first class degree in Natural Sciences.

During the First World War he joined the West Riding Regiment, and later transferred to the Royal Engineers. After returning from active service in World War I, Appleton became assistant demonstrator in experimental physics at the Cavendish Laboratory in 1920. He was professor of physics at King’s College London (1924–36) and professor of natural philosophy at Cambridge University (1936–39). From 1939 to 1949 he was secretary of the Department of Scientific and Industrial Research. Knighted in 1941, he received the 1947 Nobel Prize in Physics for his contributions to the knowledge of the ionosphere, which led to the development of radar.

From 1949 until his death in 1965, he was Principal and Vice-Chancellor of the University of Edinburgh. In 1956, the BBC invited him to deliver the annual . Across a series of six radio broadcasts, titled , Appleton explored the many facets of scientific activity in Britain at the time.

Honours and awards

  • Fellow of the Royal Society (1927)
  • Foreign Honorary Member of the American Academy of Arts and Sciences (1936)
  • Nobel Prize in Physics (1947)

Works

Appleton had observed that the strength of the radio signal from a transmitter on a frequency such as the medium wave band and over a path of a hundred miles or so was constant during the day but that it varied during the night. This led him to believe that it was possible that two radio signals were being received. One was traveling along the ground, and another was reflected by a layer in the upper atmosphere. The fading or variation in strength of the overall radio signal received resulted from the interference pattern of the two signals.

The existence of a reflecting atmospheric layer was not in itself a completely new idea. Balfour Stewart had suggested the idea in the late nineteenth century to explain rhythmic changes in the earth’s magnetic field. More recently, in 1902, Oliver Heaviside and A.E. Kennelly had suggested such a hypothesis may explain the success Marconi had in transmitting his signals across the Atlantic. Calculations had shown that natural bending of the radio waves was not sufficient to stop them from simply “shooting off” into empty space before they reached the receiver.

Appleton thought the best place to look for evidence of the ionosphere was in the variations he believed it was causing around sunset in radio signal receptions. It was sensible to suggest these variations were due to the interference of two waves but an extra step to show that the second wave causing the interference (the first being the ground wave) was coming down from the ionosphere. The experiment he designed had two methods to show ionospheric influence and both allowed the height of the lower boundary of reflection (thus the lower boundary of the reflecting layer) to be determined. The first method was called frequency modulation and the second was to calculate the angle of arrival of the reflected signal at the receiving aerial.