Matter, energy, electricity, light which were formerly considered as continuous quantities were found to be discrete: there are particles of matter elementary particles , energy quanta, Planck , electricity electron , light photons. Radioactive decay, particle interactions imposed a probabilistic physics which progressively replaced classic deterministic physics. Radioactivity can be used as a clock to measure time in the universe.
Datations were made for fossils, art masterpieces and also for the earth, the solar system and universe. X-rays diffraction proved to be a powerful tool for studying crystals and molecules, in particular protein, and in enabled to demonstrate the DNA double helix.
Hence X-rays and radioactivity originated a revolution in physics and science and in the vision of nature. As a student in Holland, he was expelled from the Utrecht Technical School for a prank committed by another student. He was particularly interested in cathode rays and in assessing their range outside of charged tubes.
On November 8, , Roentgen noticed that when he shielded the tube with heavy black cardboard, the green fluorescent light caused a platinobarium screen nine feet at away to glow - too far away to be reacting to the cathode rays as he understood them. He determined the fluorescence was caused by invisible rays originating from the Crookes tube he was using to study cathode rays later recognized as electrons , which penetrated the opaque black paper wrapped around the tube.
Further experiments revealed that this new type of ray was capable of passing through most substances, including the soft tissues of the body, but left bones and metals visible. One of his earliest photographic plates from his experiments was a film of his wife Bertha's hand, with her wedding ring clearly visible. To test his observations and enhance his scientific data, Roentgen plunged into seven weeks of meticulous planned and executed experiments.
In January he made his first public presentation before the same society, following his lecture with a demonstration: he made a plate of the hand of an attending anatomist, who proposed the new discovery be named "Roentgen's Rays. The news spread rapidly throughout the world. Thomas Edison was among those eager to perfect Roentgen's discovery, developing a handheld fluoroscope, although he failed to make a commercial "X-ray lamp" for domestic use.
For the first time in 40 years, the Republican Party wins control of both the U. House of Representatives and the Senate in midterm congressional elections. Sign up now to learn about This Day in History straight from your inbox. Doc Holliday—gunslinger, gambler, and occasional dentist—dies from tuberculosis.
Though he was perhaps most famous for his participation in the shootout at the O. Mitchell worked as a journalist for the Atlanta Journal for six years.
She quit after an ankle injury limited her mobility, and she devoted herself to her novel about the DaRonch had been shopping at a mall when a man claiming to be a police detective told her that there was an attempted theft of her car and she needed to file a police report. John F. Kennedy, 43, becomes the youngest man ever to be elected president of the United States, narrowly beating Republican Vice President Richard Nixon.
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