- In full:
- Sir William Henry Bragg
- Born:
- July 2, 1862, Wigton, Cumberland, Eng.
- Died:
- March 12, 1942, London (aged 79)
- Awards And Honors:
- Copley Medal (1930)
- Nobel Prize (1915)
- Notable Family Members:
- son Sir Lawrence Bragg
- Subjects Of Study:
- Bragg ionization spectrometer
Sir William Bragg
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Who was Sir William Bragg?
Sir William Bragg (1862–1942) was a distinguished British physicist and solid-state physics pioneer. In 1915, he shared the Nobel Prize for Physics with his son, Sir Lawrence Bragg, for their groundbreaking research in determining crystal structures.
Bragg's early career included roles as a professor of mathematics and physics at the University of Adelaide, where he honed his skills in lecturing and instrument making. His work on alpha, beta, and gamma rays led to his election as a Fellow of the Royal Society in 1907. Later, he became a professor in Leeds, England, contributing significantly to understanding X-ray behavior.
After World War I, Bragg established a crystallographic research school at University College, London and directed the Royal Institution and the Davy Faraday Research Laboratories. He was also known for his engaging science lectures and writings, including "Christmas Lectures" for children. He served as President of the Royal Society from 1935 to 1940 and received numerous honors.
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What is Sir William Bragg known for?
Sir William Bragg (1862–1942) was a pioneer British scientist celebrated for his contributions to solid-state physics. In 1915, he and his son, Sir Lawrence Bragg, jointly received the Nobel Prize for Physics for their groundbreaking research on determining crystal structures using X-ray diffraction.
Bragg's early career involved teaching mathematics and physics at the University of Adelaide, where he honed his skills in lecturing and instrument making. His work with alpha, beta, and gamma rays led to his election to the Royal Society in 1907. Later, he developed the view that gamma rays and X-rays have particle-like properties. He also designed the Bragg ionization spectrometer, which enabled precise measurements of X-ray wavelengths and crystal data.
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What is X-ray crystallography, and how did Bragg contribute to it?
X-ray diffraction, or X-ray crystallography, is a phenomenon where the atoms within a crystal cause an interference pattern when X-rays pass through. This method allows scientists to deduce the crystal's internal structure by observing the interference pattern.
Sir William Bragg and his son, Lawrence, significantly contributed to this field. In 1912, Max von Laue discovered that crystals could diffract X-rays, suggesting X-rays behave like waves with short wavelengths. The Braggs then applied X-rays to study crystal structure, earning them the Nobel Prize in Physics in 1915. Their work led to the development of the X-ray powder diffractometer, now widely used to identify minerals and ascertain their crystal structure. Bragg's law defines the relationship between the angle of incidence, X-ray wavelength, and the distance between crystal planes.
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How did Sir William Bragg work with his son, Lawrence Bragg?
Sir William Bragg and his son, Lawrence Bragg, jointly won the Nobel Prize in Physics in 1915 for their work on determining crystal structures. In 1912, after Max von Laue discovered that crystals could diffract X-rays, the Braggs began to use X-rays to study crystal structure. William designed the Bragg ionization spectrometer, the prototype of modern X-ray and neutron diffractometers, which allowed for the first measurements of X-ray wavelengths and crystal data. After World War I, William established a crystallographic research school at University College, London.
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What important award did Sir William Bragg and his son win together?
Sir William Bragg and his son, Sir Lawrence Bragg, jointly won the Nobel Prize for Physics in 1915 for their research on crystal structures. William Bragg was a pioneer in solid-state physics. In 1912, Max von Laue discovered that crystals could diffract X-rays. Following this discovery, Bragg and his son explored the application of X-rays to study crystal structure, which led to their Nobel Prize.
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How has Sir William Bragg’s work influenced modern science and technology?
Sir William Bragg, a pioneer in solid-state physics, significantly shaped modern science and technology through his work on crystal structures. In 1912, he and his son, Lawrence Bragg, demonstrated that crystals could diffract X-rays, implying X-rays are waves with short wavelengths.
Bragg designed the Bragg ionization spectrometer, which allowed for the first measurements of X-ray wavelengths and crystal data. This became the prototype for modern X-ray and neutron diffractometers. The Bragg law is useful for measuring wavelengths and determining the lattice spacings of crystals.
Bragg's work laid the foundation for X-ray crystallography, which allows chemists to determine the internal structures and bonding arrangements of minerals and molecules, including large, complex ones like proteins and DNA. This has been critical in understanding the mechanisms of enzymes and other proteins.
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Sir William Bragg (born July 2, 1862, Wigton, Cumberland, Eng.—died March 12, 1942, London) was a pioneer British scientist in solid-state physics who was a joint winner (with his son Sir Lawrence Bragg) of the Nobel Prize for Physics in 1915 for his research on the determination of crystal structures. He was knighted in 1920.
William Bragg came on his father’s side from a family without academic traditions, mainly yeoman farmers and merchant seamen. His mother was the daughter of the local vicar. Upon her death, when he was barely seven, he went to live with two paternal uncles who had set up a pharmacy and grocery shop in Market Harborough, Leicestershire. There he attended an old school reestablished by one of his uncles. He did well, and in 1875 his father sent him to school at King William College, Isle of Man. At first he found it difficult to adjust himself, but he was good at his lessons and at sports and finally became head boy. During his last year, however, the school was swept by a storm of religious emotionalism. The boys were frightened by the stories of hellfire and eternal damnation, and the experience left a strong mark on Bragg. Later he wrote, “It was a terrible year . . . for many years the Bible was a repelling book, which I shrank from reading.” And in a lecture, Science and Faith, at Cambridge in 1941, he said, “I am sure that I am not the only one to whom when young the literal interpretation of Biblical texts caused years of acute misery and fear.” On the other hand, he attributed his clear, balanced style of writing to his early grounding in the Authorized (King James) Version of the Bible; in The World of Sound he wrote, “From religion comes a man’s purpose; from science his power to achieve it.”
In 1882 he was granted a scholarship at Trinity College, Cambridge; and two years later he obtained third place in the Mathematical Tripos (final examinations), a splendid achievement that led to his appointment, in 1885, as professor of mathematics and physics at the young University of Adelaide, S.Aus. He then not only trained himself to become a good, lucid lecturer but also apprenticed himself to a firm of instrument makers and made all the equipment he needed for practical laboratory teaching. It was this early training that enabled him, later (in 1912), after his return to England, to design the Bragg ionization spectrometer, the prototype of all modern X-ray and neutron diffractometers, with which he made the first exact measurements of X-ray wavelengths and crystal data.
It was not until 1904, when Bragg became president of the physics section of the Australian Association for the Advancement of Science, that he began to think about original research. His subsequent work on alpha, beta, and gamma rays led the renowned British physicist Ernest Rutherford to propose him for fellowship of the Royal Society. He was elected in 1907 and within a year was offered a professorship in Leeds, England, where he developed his view that both gamma rays and X rays have particle-like properties.
In 1912 the German physicist Max von Laue announced that crystals could diffract X rays, thus implying that X rays must be waves like light but of much shorter wavelength. Bragg and his elder son, Lawrence, who was studying physics at Cambridge, then began to apply X rays to the study of crystal structure. These researches earned them jointly the award of the Nobel Prize for Physics in 1915.
After World War I, during which he worked on anti-submarine devices, Bragg established a school of crystallographic research at University College, London, and then, upon the death of the chemist and physicist Sir James Dewar, succeeded him as director of the Royal Institution and of the Davy Faraday Research Laboratories, London. To these institutions he attracted many young scientists whose researches he inspired and stimulated and who subsequently achieved fame. Bragg was also a popular scientific lecturer and writer. He gave “Christmas Lectures” for children, which, when published, became best-sellers. With Lady Bragg, he established a salon to which famous scientists came from far and wide. He was president of the Royal Society from 1935 to 1940 and received many other honours, but, to the last, he remained simple, gentle, and humble about his own success and proud of his son’s.