Problem: Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. He produced solid hydrogen the next year. Deuterium was discovered in December 1931 by Harold Urey, and tritium was prepared in 1934 by Ernest Rutherford, Mark Oliphant, and Paul Harteck. Heavy water, which consists of deuterium in the place of regular hydrogen, was discovered by Urey's group in 1932. Francois Isaac de Rivaz built the first de Rivaz engine, an internal combustion engine powered by a mixture of hydrogen and oxygen in 1806. Edward Daniel Clarke invented the hydrogen gas blowpipe in 1819. The Dobereiner's lamp and limelight were invented in 1823.
Who was the first to liquidize hydrogen?
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Answer: James Dewar

Problem: As an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to the source, forming a standing wave in the feed line. The ratio of maximum power to minimum power in the wave can be measured and is called the standing wave ratio (SWR). A SWR of 1:1 is ideal. A SWR of 1.5:1 is considered to be marginally acceptable in low power applications where power loss is more critical, although an SWR as high as 6:1 may still be usable with the right equipment. Minimizing impedance differences at each interface (impedance matching) will reduce SWR and maximize power transfer through each part of the antenna system.
What is created by a portion of a radio waves energy reversing?
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Answer: standing wave

Problem: Widowed in 1861, the grief-stricken Queen withdrew from public life and left Buckingham Palace to live at Windsor Castle, Balmoral Castle and Osborne House. For many years the palace was seldom used, even neglected. In 1864, a note was found pinned to the fence of Buckingham Palace, saying: "These commanding premises to be let or sold, in consequence of the late occupant's declining business." Eventually, public opinion forced the Queen to return to London, though even then she preferred to live elsewhere whenever possible. Court functions were still held at Windsor Castle, presided over by the sombre Queen habitually dressed in mourning black, while Buckingham Palace remained shuttered for most of the year.
Which house did Queen Victoria stay at after she left Buckingham?
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Answer:
Osborne House