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Lise Meitner 1878 - 1968 PowerPoint Presentation
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Lise Meitner 1878 - 1968

Lise Meitner 1878 - 1968

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Lise Meitner 1878 - 1968

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  1. Lise Meitner1878 - 1968 A physicist who never lost her humanity

  2. The most significant woman scientist of the 20th century • Born in Vienna, Austria in a Jewish family • First person to realize that the nucleus of an atom could be split into smaller parts. • Element 109, Heaviest known element in the universe bears her name Meitnerium.

  3. First woman to earn a doctoral degree in physics at the university of Vienna. • Was actively involved in the scientific field since 1917, culminating into discovery of an isotope of Protractinium with Chemist Otto Hahn. • With her own physics section at the Kaiser Wilhelm institute of chemistry, she went on and discovered the cause of the Auger Effect (Emissions from surfaces of electrons with signature energies.)

  4. The discovery of neutrons, and speculation about the possibility of synthesizing heavier elements than uranium triggered the Nuclear Race involving some of the great scientists at the time like Ernest Rutherford, Otto Hahn etc..

  5. When Adolf Hitler came to power in 1933, all her colleagues and top jewish scientists were forced to resign from their posts. But she maintained immunity due to her Austrian citizenship. Instead of leaving or saying something, she totally immersed herself in her work which she openly later voiced regrets about. • In the july of 1938, with the help of a dutch physicist named costner, she emigrated into hollands after losing her citizenship during the Anschluss. An anecdote about this is that her great friend and chemist otto hahn gave her a diamond ring passed down from his mother to be used to bribe the frontier guards if need be. She openly professed that she made it to Holland with 10 marks, without her belongings.

  6. She had a chance to work with the likes of Niers Bohr in stockholm, and Max Planck and faced constant prejudice in a male dominated world of science. • She was 1st person to realize that the nucleus of an atom could be split into smaller parts: • The Uranium nuclei for example splits to form barium and Krypton, accompanied by ejection of several neutrons and mass amounts of Energy.(account for loss in mass). • This release of energy triggers an ongoing chain reaction with energy levels exponentially growing.

  7. To have somewhat of an idea about Nuclear Fission, you must understand a few basic Principles. • Chemicalisotopes that can sustain a fission chain reaction are called nuclear fuels, and are said to be fissile. • The most common nuclear fuels are 235U (the isotope of uranium with an atomic mass of 235 and of use in nuclear reactors) and 239Pu (the isotope of plutonium with an atomic mass of 239). • These fuels break apart into a range of chemical elements with atomic masses near 100 (fission products). Most nuclear fuels undergo spontaneous fission only very slowly, decaying mainly via an alpha/betadecay chain over periods of millennia to eons. In a nuclear reactor or nuclear weapon, most fission events are induced by bombardment with another particle such as a neutron

  8. Typical fission events release several hundred billion eV of energy for each fission event. By contrast, most chemicaloxidation reactions (such as burning coal or TNT) release at most a few eV per event, so nuclear fuel contains at least ten million times more usable energy than does chemical fuel. • Nuclear fuels are made to undergo induced fission by bombardment with excess neutrons

  9. Even the first fission bombs were thousands of times more explosive than a comparable mass of chemical explosive. For example, Little Boy weighed a total of about four tons (of which 60 kg was nuclear fuel) and was 11 feet long; it also yielded an explosion equivalent to about 15,000 tons of TNT, destroying a large part of the city of Hiroshima. • Modern nuclear weapons (which include a thermonuclear fusion as well as one or more fission stages) are literally hundreds of times more energetic for their weight than the first pure fission atomic bombs, so that a modern single missile warhead bomb weighing less than 1/8th as much as Little Boy (see for example W88) has a yield of 475,000 tons of TNT, and could bring destruction to 10 times the city area.

  10. Discovery of nuclear power had an electrifying effect on the scientific community, and its capacity as a weapon especially in the hands of the Nazi Regime wasn’t that good of an idea. • Edward Teller and Eugene Wigner persuaded Einstein(who was popular) to write a letter to Franklin D. Roosevelt which was basically a catalyst for the Manhattan project. • A Nuclear Weapon is basically a fission reactor designed to release as much energy as possible and as rapidly as possible before released energy destroys the reactor, therefore stopping the chain reaction.

  11. And What would Meitner Do ?

  12. HECK NO!!!!!!!

  13. She lost her Nobel prize to Han(for chemistry) in 1944 for the discovery of Nuclear Fission. Most of the experiments in her collaborative work with Hanh took place in Hahn’s lab in Germany due to her exiled status. • Hahn published his lab findings in January 1939, but couldn’t explain the physics of it which was done so by Meitner in February of the same year.

  14. Lise's Grave in Bramley "You all worked for Nazi Germany. And you tried to offer only a passive resistance. Certainly, to buy off your conscience you helped here and there a persecuted person, but millions of innocent human beings were allowed to be murdered without any kind of protest being uttered... [it is said that] first you betrayed your friends, then your children in that you let them stake their lives on a criminal war - and finally that you betrayed Germany itself, because when the war was already quite hopeless, you did not once arm yourselves against the senseless destruction of Germany