P1

P1

1. Particles

   • Atoms
     • Isotopes
       • Different number of neutrons same number of protons and electrons
     • Specific Charge
       • Charge (C)/mass (kg)
     • Radiation
       • Gamma
         • EM wave, v high freq
       • Alpha
         • Helium nucleus (2p, 2n)
       • Beta
         • Electron/positron
   • Fundamental Forces
     • Strong
       • Repulsive below 0.5 fm
       • attractive up to 3-4 fm
       • Holds nuclei together
     • Weak
       • The interaction force within unstable nuclei when decay occurs
     • Electromagnetic
       • between charged particles
   • Photons
     • Wave particle duality
     • Wavelength = c/f
     • E=hf
     • P=nhf
   • Interaction
     • Annihilation
       • particle & antiparticle > 2 photons
         • 2 to conserve momentum
       • hf=E
     • Pair production
       • photon > particle & antiparticle
       • hf=2E
     • Feynman diagrams
   • Types
     • Hadrons
       • Baryons
         • Proton
           • Charge; 1.6 x10-19
           • Mass; 1.67x10-27
         • Neutron
           • No Charge
           • Mass; 1.67x10-27
       • Mesons
         • Pi
         • K
           • Are strange
     • Leptons
       • Electron
         • Charge; 1.6 x10-19
         • Mass; 9.11x10-31
       • muon
       • neutrino
   • Quarks
     • u
     • d
     • s

2. Quantum Phenomena

   • Photoelectricity
     • Ek=hf-(work function)
     • f(min)=(work function)/h
     • More intense light will not enable photoelectric effect, rather will increase the number of electrons per second
   • Collisions
     • Ionisation
     • Excitation
       • 2 electrons
         • Photons can also cause
       • Multiple levels for each electron
         • will release photons equal to one or multiple levels when de-excited
   • Spectra
     • Each element produces its own unique spectra
   • Wave particle duality
     • Diffraction
     • (de broglie wavelength)=h/p=h/mv

3. Electricity

   • Current
     • The amount of charge per unit of time
   • Equations
     • I=Q/t
     • V=W/Q
     • W=IVt
     • P=IV
     • R=V/I
     • heat transfer=I^2*R
     • emf=IR+Ir
   • Voltage
     • Work done per charge
   • Resistance
     • Ohms Law;
       • The pd across a conductor is proportional to the current through it
     • (resistivity)=RA/L
     • In series
       • Add
     • Parallel
       • 1/R0=1/R1+1/R2
   • Circuit rules
     • Current is split but not used up
     • Voltage is not split but is used up
       • sum of emf's=sum of potential drops
   • AC
     • rms=peak/sqrt(2)
     • oscilliscope
       • time base