Interesting quotes from Niels Bohr

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Niels Bohr
Interesting quotes from Niels Bohr Anyone who
is not shocked by quantum theory has not
understood it An expert is a man who has made
all the mistakes which can be made in a very
narrow field
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(No Transcript)
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A Brief History of Niels Bohr Born in
1885 Bohrs father was a professor of physiology
in Denmark. His brother became a renowned
mathematician In 1911, Bohr received his
doctorate in Physics Bohr went to work in J. J.
Thomsons lab as a theoretical physicist. He next
worked in Ernest Rutherfords lab.
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A Brief History of Niels Bohr, continued It
was in Rutherfords lab Bohr developed his model
of the atom improving the Rutherford model He
was awarded the Nobel Prize in Physics
(1922) Debated quantum mechanics with Einstein
in the 20s Left Denmark (and escaped the
Germans) at the beginning of WWII and spent time
at Los Alamos during atomic bomb development
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What was the Rutherford Model? Remember the Gold
Foil Experiment? What did Rutherford conclude
about the atom?
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and Rutherford got a Nobel Prize in CHEMISTRY!!
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-The Rutherford Model had a small area of
positive charge -Most of the atom is empty
space -Cloud of electrons orbit the area of
positive charge (Rutherford originally did not
use the term nucleus)
One representation of the Rutherford Model
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Another representation of Rutherfords cloud of
electrons
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Problem with the Rutherford Model This model
couldnt exist based on classical mechanics (from
Newton) Electrons should lose energy and
collapse into the nucleus
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Niels Bohr was a theoretical physicist. That is,
he used data from other scientists instead of
performing experiments. Bohr saw the problem
with the Rutherford model and classical
mechanics. He added the concept of energy in
quanta from Planck to Rutherfords Model. This
helped to explain the emission spectrum of
hydrogen
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Main Concepts of Bohrs Model 1. Electrons
assume only certain orbits around the nucleus.
These orbits are stable and called "stationary"
orbits. 2. Each orbit has an energy associated
with it. For example the orbit closest to the
nucleus has an energy E1, the next closest E2 and
so on. 3. Light is emitted when an electron
jumps from a higher orbit to a lower orbit and
absorbed when it jumps from a lower to higher
orbit. Only whole number jumps allowed.
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Main Concepts of Bohrs Model 4. The energy
and frequency of light emitted or absorbed is
given by the difference between the two orbit
energies.
A picture of Bohrs model
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Bohrs model did an excellent job explaining
hydrogen emission spectrum but was inadequate to
explain any other element.
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On to quantum mechanics..
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Resources
http//nobelprize.org/nobel_prizes/physics/laureat
es/1922/bohr-bio.html http//www.pbs.org/wgbh/aso
/databank/entries/bpbohr.html http//www.crystali
nks.com/bohr.html http//www.answers.com/topic/ni
els-bohr