nuclear power
TRANSCRIPT
NUCLEAR POWER
History of Nuclear Physics and Weapons;
Nuclear Power Today
By: Evelina Skarp & Martha van Schaik, 9C
Introduction
Nuclear power was discovered over 100 years ago.
Everything related to nuclear power has not been a positive invention.
Right now nuclear power is being developed towards the benefit of mankind.
Introduction to the Basic History of Nuclear Physics
The late 20’s and early 30’s are known for discovering radioactivity and the huge steps forward in the techniques and instrumentation of nuclear physics.
Scientists had to create large electric fields to be able to continue their research.
1930’s- Ernest Lawrence invented the cyclotron (=circular magnetic accelerator).
Nuclear Physics
Basic History It is very difficult to
date the birth of nuclear physics.
The year 1932 is considered to be the birth year of nuclear physics due to the discovery of the neutron, positron, deuteron and the completion of the first particle accelerator.
1896- Henri Becquerel accidentally discovered radioactivity
1898- Marie and Pierre Curie discovered radium and polonium
1920’s- A. Eddington, R. Atkinson and F. Houtermans suggested that the Sun’s steady energy release was due to nuclear fusion reactions
1928- G. Gamow, E. Condon and R. Gurney showed that charged particles have enough energy to penetrate a nucleus and cause its disintegration.
1932 is considered to be the “birth”
of Nuclear Physics
Fission Fission is the splitting of a heavy nucleus
into lighter nuclei. Does not require a lot of energy. The energy released by fission is many
times greater than the energy released by a chemical reaction.
Fusion Fusion is the fusing of
light nuclei into a heavier nucleus.
It requires a lot of energy to bring the protons close enough to overcome their electrostatic repulsion.
The energy released by fusion is many times greater than the energy released by nuclear fission.
Nuclear Weaponsfission and fusion weapons
Atomic Bomb in History The first person who
seriously started to think about the possibility of an atomic bomb was Leó Szilárd (1898-1964) in the 1930’s.
USA were first to invent the atomic fission bomb. Russians stole the technology.
Nazi Germany was the first to start the development of an atomic bomb
1944 – invention of atomic bomb (USA)
1945, 6 of August, 8:15 – the first atomic explosion in Hiroshima (USA) (Little Boy)
1949- USSR tested their first fission weapon
Atomic Bomb, Little Boy Fission weapons get
their energy by blasting u-235 (an isotope of uranium) together forming a chain reaction. When the u-235 is blasted the nuclei split, giving out energy
Atomic Bomb, Fat Man There is another way
to form critical mass. Using shock-waves
from shaped explosives the sub-critical mass is compressed. Fewer electrons are lost and the chain reaction begins
Hydrogen Bomb Idea to create a more
powerful fusion weapon appeared in 1950s.
This was the time of the Cold War so it is hard to tell who was first in the H-bomb development.
American sources say that they have performed a first explosion on the 1 of November of 1952.
Russian sources say that they made it on the 21 of September 1955 and that USA made it in 1956 at Bikini
Deuterium and/or tritium are the fuel of a fusion weapon. It would have been risky to store either of these gases in a bomb. This problem was solved when scientists figured out that lithium could be turned into tritium by adding one neutron. A fusion bomb works by having a fission bomb as a trigger. When the fission bomb explodes, it gives out heat and neutrons, which turn the lithium into tritium, and compresses the tritium
First Nuclear Power Plant The rapid development of nuclear power
was due to the nuclear arms race between USA and USSR during the Cold War.
After the war people started thinking of domestic uses for nuclear power, thus inventing commercial power plants.
December 1951- the first electricity was generated from atomic power at EBR-1 Idaho National Engineering Lab, Idaho Falls, USA
June 1954- the world’s first nuclear power plant to generate electricity for commercial use, APS-1, was connected to the power grid at Obninsk, Russia.
August 1956- the world’s first commercial power plant, Calder Hall 1, was connected to the power grid in England.
December 1957- USA’s first commercial power plant, Shippingport, goes into use in Pennsylvania.
FrontiersBiographies
Henri Becquerel(1852–1908)
Was a French physicist. Born on 15th of
December 1852 in Paris, France.
Best known for discovering radioactivity in 1896.
Discovered radioactivity by putting a key that was under some dark piece of paper in a closet that had radioactive material in it.
Sir Ernest Rutherford(1871–1937)
Was a British physicist-chemist.
Born on 30th August 1871 in Nelson, New Zealand.
In the late 1890’s he suggested that the disintegration of atoms results in radioactivity.
In 1917 he discovered that the nuclei of light elements can be disintegrated, leading to the discovery of alpha and beta particles.
Sir James Chadwick(1891–1974)
Was a British physicist.
He was born 20th October 1891 in Cheshire, England.
He helped Rutherford with the properties and structure of atomic nuclei.
In 1932 he proved the existence of neutrons.
George Gamow(1904–1968)
Was an American physicist-theorist and astronomer.
He was born on 4 of March in 1904 in Odessa, USSR.
His first success was the formation of the fusion theory.
He lived and worked in USA. He was the first one to work out
star models with thermonuclear sources of energy.
He did research on alpha decay. He made a model of the “Hot
Universe”. He was the first to formulate the
problem of the genetic code. He died on 19 of August in 1968, in
Colorado, USA.
Further Development of Nuclear PowerToday nuclear physics is developing in a more peaceful directionWe are starting to become more and more dependant on nuclear power. Nuclear power produces more than 25% of the total electricity made in over 15 countries There is a total of about 440 nuclear reactors around the world.
Nuclear Weapons Policies
After the end of Cold War, USA, G-7 and Russia established the Cooperative Threat Reduction Programs to:
- dismantle strategic nuclear weapons
- strengthen the security of nuclear weapons and materials
- employ key scientists in weapons of mass destruction (WMD) complexes.
Russia and USA did not become allies. Despite the signed agreement of de-targeting, each country has suspicions over other’s missiles explaining the sizes of their nuclear arsenals.
Nuclear Power Stations in the World
Pros & Cons
Dangerous
Very Polluting
Can destroy ozone layer
Can change climate
-Cheap to get
Easy to get
Has many uses
Most effective electricity source
Possible to make it a future source of energy
+ Many oppose nuclear
power. The example how dangerous it is the disaster in Chernobyl.
http://www.youtube.com/watch?v=m2jL5ubnd8g&feature=related
In future scientists are planning to use fusion as an ecological source of energy
http://www.youtube.com/watch?v=vDAZsPkTkMM
Conclusion
Nuclear power was discovered over 100 years ago.
It has developed at a rapid speed thanks to the invention of nuclear arms.
Everything related to nuclear power has not been a positive invention
Now nuclear power is being developed towards the benefit of mankind.
Bibliography Frontiers. twentieth-century physics, Steve Adams, 2000, London and New
York BSE (Big Soviet Encyclopedia, huge list of authors,) The Dictionary of Battles. the world's key battles from 405 BC to today,
general editor David Chandler, 1987, Ebury Press, London Building the Universe, a new scientist guide. edited by Christine Sutton, 1985,
Oxford http://www.hps.org/publicinformation/ate/q1662.html http://www.euronuclear.org/info/npp-ww.htm http://www.diffen.com/difference/Nuclear_Fission_vs_Nuclear_Fusion http://www.hep.man.ac.uk/babarph/babarphysics/positron.html http://science.howstuffworks.com/nuclear-bomb6.htm http://www.bbc.co.uk/history/historic_figures/rutherford_ernest.shtml http://www.huwu.org/nobel_prizes/physics/laureates/1935/chadwick-bio.html http://nobelprize.org/nobel_prizes/physics/laureates/1951/cockcroft-bio.html http://en.wikipedia.org/wiki/Ernest_Walton http://nobelprize.org/nobel_prizes/physics/laureates/1951/walton-bio.html http://www.world-nuclear.org/why/nuctoday.html http://www.world-nuclear.org/info/reactors.html