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Particle Physics
Question | Answer |
---|---|
What three things are conserved in nuclear reactions? | Mass-energy, momentum, and electric charge. |
Why is the neutrino hard to detect? | It only interacts very weakly with matter |
Who first split a nucleus by artificially accelerated particles? | John Cockroft and Ernest Walton |
What did Cockroft and Waltons experiment verify | E=mc^2 |
Define pair production | The creation of a particle and its antiparticle from energy with momentum and electric charge being conserved |
Define pair annihilation | When a particle and its antiparticle are almost at rest near each other they join together to create two photons of equal energy travelling in opposite directions. |
Name the four forces in increasing order of strength | Gravity, weak nuclear force, electromagnetic, strong nuclear force |
What is the range of strong nuclear force | 10^-15 meters |
What is the range of weak nuclear force | 10^-18 meters |
What is the range of electromagnetic force | infinite |
What is the range of gravity | Infinite |
What particles feel strong nuclear force | Hadrons |
Name two groups of elementary particles | Leptons & Quarks |
Name two members of the Hadron family | Baryons & Mesons |
Name the six flavours of Quarks | Up, down, charmed, strange, top, bottom |
What are mesons made from | A quark and anti quark |
What are Baryons made of | Any three quarks or anti quarks |
What is the composition of a proton | UUD |