nuclear
TRANSCRIPT
The Science Behind Nuclear Power
Atoms are made of a nucleus that contains PROTONS & NEUTRONS
Whizzing around the outside are ELECTRONS
The Science Behind Nuclear Power
1. Fission
If you split the nucleus of an atom there is a release of energy. This is known as nuclear FISSION
This can be done by firing a neutron at the nucleus
As the nucleus splits it releases more neutrons which go on to split more atoms. This causes a chain reaction.
The Science Behind Nuclear Power
1. Fission
In a nuclear power station this chain reaction is controlled and the energy that is released is used to turn liquid water into steam which, in turn, turns a generator to produce electrical energy. The big advantage is that it does not produce any CO2
In a nuclear bomb the chain reaction is not controlled which is what causes the massive explosion
The Science Behind Nuclear Power
2. Nuclear Fusion
Fusion is the opposite of fission. This time 2 atoms are combined to make 1 new atom.
It is normally 2 Hydrogen (H) atoms that are combined to form 1 atom of Helium (He).
As the atom of Helium (He) is produced there is a release of energy.
Nuclear fusion is a lot more difficult to achieve than fission.
Nuclear Power The Problems
1. Power Stations
Spent nuclear fuel remains dangerous for centuries. It is very expensive and difficult to dispose of it in a safe way.
When something goes wrong it can go wrong in a big way.
Nuclear Power The Problems
Chernobyl 26th April 1986
At 01.23 a fire in the power station causes a huge explosion which in turn leads to a core melt down (where the nuclear chain reaction gets out of control).
The explosion blew the protective lid off the reactor sending radioactive material 1km up into the sky.
This was then blown west across Europe and effected many countries including the UK.
Nuclear Power The Problems
2. Nuclear Bombs
Nuclear bombs are just so powerful. They have the potential to destroy entire cities in one go.
They leave radioactive fall out long after the initial explosion.
They have only been used in anger twice.
Nuclear Power The Problems
Hiroshima & Nagasaki 1945
Towards the end of the second world war the USA forced the Japanese into surrender by using 2 atomic bombs.
The first was called “Little Boy” and was dropped on the city of Hiroshima on the 6th August 1945 by a bomber called the Enola Gay.
The result was that 80,000 people were killed and 68% of buildings were destroyed in the initial blast. In the following months a further 60,000 people died from injuries and radioactive poisoning.
Nuclear Power The Problems
3 days later on the 9th August a 2nd bomb called “Fat Man” was dropped on the city of Nagasaki.
As in Hiroshima the city was destroyed and 74,000 people killed
On the 15th August Japan surrendered to the USA.
For many years afterwards survivors from both bombs have been suffering the effects of radioactivity.
List of Countries With Nuclear Weapons
Country Number of Warheads
Date of 1st Test
USA 9,960 1945
Russia 16,000 1949
UK 200 1952
France 350 1960
China 130 1964
India 50 1974
Pakistan 52 1998
North Korea
10 2006
Israel 200 1979
J. Robert Oppenheimer
“Father” of the bomb speaking after the bombing
The devastating effect of a nuclear blast on buildings
The thermal pulse that arrives just prior to the blast.
Footage of the bomb exploding in Nagasaki
American footage of the bomb on Hiroshima
Detonation of a bomb by the USA on the Bikini atoll