Strong Nuclear Force vs. Weak Nuclear Force

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Strong Nuclear Force vs. Weak Nuclear Force
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Similarities

• Both one of the four fundamental forces that
  governs how the universe works
• Both work at a subatomic level
• Both have a very short range

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Strong Nuclear Force

• Holds quarks together to form protons and
  neutrons
• Gluons mediate the force

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Residual Strong Nuclear Force

• Other form called residual strong nuclear force
• Affects neutrons and protons
• Works against electromagnetism
• Keeps nucleuses together, mediated by mesons

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Strong Force Meets Weak Force

• Needs right amount of neutrons and protons for a
  nucleus to stay stable
• Too many protons (positively charged particles),
  electromagnetism is too strong, overwhelms strong
  force
• Too many neutrons strong force squeezes too
  tightly

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Strong Force Meets Weak Force (contd)

• This instability usually occurs in very large and
  dense atoms such as uranium and plutonium
• Instability can cause one of three things
• Alpha decay
• Beta decay
• Spontaneous fission

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Alpha Decay

• Atoms give off an alpha particle
• Helium-4 nucleus
• Two protons two neutrons
• Can be stopped by skin or paper
• Dangerous if ingested, will cause internal damage

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Spontaneous Fission

• This happens when an atom randomly breaks apart
  to form two totally different nucleuses

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Nuclear Fission

• One usually smaller atom hits a bigger atom
• Nuclear power works by bashing atoms together so
  that they split therefore using Einsteins
  Relativity giving off huge amounts of energy
• This energy is then usually used to heat water
  and so the process goes
• If when the atoms break apart they collide with
  more atoms (about the amount of atoms the size
  of a basketball) causing a massive chain reaction
  effects are devastating
• The nuclear bomb

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Beta Decay

• This is what the equation for weak nuclear force
  explains
• The reason why beta decay occurs

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Beta Decay (contd)

• W negative, W positive, Z neutral
• These cause one type of quark to turn into
  another and in the end cause one neutron to turn
  into a proton or vice versa.
• When a neutron turns (which has no charge) turns
  into a proton (which has a positive charge) there
  has to be something that balances the equation
  and those things are electrons, positrons,
  neutrinos and antineutrinos
• When the neutron becomes a proton (this is called
  positive beta decay) the atom gives off an
  electron and an antineutrino
• When a proton becomes a neutron (this is called
  negative beta decay) the atom gives off a
  positron and a neutrino
• The positron is the opposite of an electron and a
  neutrino is the opposite of an antineutrino
• The positron has a positive charge while an
  electron has a negative charge
• The neutrinos and antineutrinos are mass less(?)
  and have no charge
• The difference between them is so slight that
  scientists have yet to discover it

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Activity

• Discuss among yourselves what a universe without
  these forces would be like

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Bibliography

• http//www.abelard.org/briefings/ionising-radiatio
  n.asp
• http//hyperphysics.phy-astr.gsu.edu/hbase/nuclear
  /beta.html
• http//en.wikipedia.org/wiki/Beta_decay