everything

• Particle groups


  • Hadrons
  • Leptons
• Leptons


  Fundamental particles including electron, muon (heavy electron), and neutrino (no charge)
• Lepton number


  Leptons have a lepton number of 1, their antiparticles have a lepton number of -1
• Neutrinos


  Can be electron neutrinos or muon neutrinos, with their own lepton numbers
• Quarks


  The 3 flavours are up, down, and strange. Up has charge +2/3, down and strange have charge -1/3
• Strangeness


  Strange quarks have strangeness -1, antistrange quarks have strangeness +1
• Baryon number


  Baryons have a baryon number of +1 or -1 if they contain antiquarks
• Neutrons are up-down-down, protons are up-up-down
• Mesons


  • Pi+ Pi0 Pi-
  • K+ K- K0
• Electromagnetic force


  Affects any charged particle, exchange particle is the photon
• Weak force


  Affects any particle, exchange particles are W+, W-, Z0 bosons
• Strong force


  Affects hadrons only, exchange particle is the gluon
• Electrostatic repulsion and strong force balance to stabilise nuclei
• Strong force range

  1. 4 fm, switches from attractive to repulsive at 0.5 fm
• In any interaction, charge, baryon number, and lepton number must be conserved
• Feynman diagrams


  Used to represent interactions, always a weak interaction for beta decay
• Strangeness must be conserved in strong interactions, but can change by 1 in weak interactions
• Charge to mass ratio

  Charge in coulombs divided by mass in kg, gives a large number
• Types of radiation


  • Electromagnetic (photons)
  • Alpha (helium nuclei)
  • Beta (electrons)
• Gamma radiation


  High energy electromagnetic radiation emitted by nuclei
• Alpha decay


  Nucleus emits 2 protons and 2 neutrons, decreasing atomic number by 2 and mass by 4
• Beta decay


  Neutron turns into proton, electron, and antineutrino, increasing atomic number by 1
• Electron-positron annihilation produces 2 photons to conserve momentum
• Pair production


  Photon with sufficient energy spontaneously converts into an electron-positron pair
• Atomic energy levels


  Electrons orbit nucleus at discrete energy levels, can be excited or ionized
• Photon energy


  Equals Planck's constant times frequency, inversely proportional to wavelength
• Emission spectrum


  Shows wavelengths of photons emitted by an object, used to identify elements
• Absorption spectrum


  Shows wavelengths absorbed by a gas or plasma, represented by dark lines
• Fluorescent tube


  Electrons accelerated through mercury gas, emit UV photons that excite fluorescent coating
• Wave-particle duality


  Photons exhibit both wave and particle properties
• Photoelectric effect


  Shining light on a metal ejects electrons, with kinetic energy related to photon frequency
• Work function


  Minimum energy required to liberate an electron from a metal surface
• Electron diffraction


  Electrons exhibit wave-like behaviour, forming interference patterns
• Electricity


  Flow of electric charge, transferring energy from a source to components
• Electric current always flows from the positive to negative terminal of a battery
• Diffraction patterns for light do not decrease to zero at certain points
• To convert between kinetic energy and momentum


  Kinetic energy = 1/2 mv^2, multiply both sides by m to get momentum squared
• Electricity is the flow of charge or charges like electrons
• Cells and batteries are the same thing and do the same job
• Battery


  Stores chemical potential energy, transfers energy to electrons which move through wires