AS - Particles And Radiation Flashcards
Equilibrium point for strong nuclear force
0.5 fm
Maximum attraction for strong nuclear force
2 fm
Nucleus Diameter
3 - 4 fm
Alpha Decay
4 He 2 nucleus
decays to give out mass
short range (5cm in air)
Beta - Decay
0 e -1 fast moving electron
Decays to change n -> p
Releases an antineutrino (takes away energy and momentum)
Beta + Decay
0 e +1 fast moving positron
Decays to change p -> n
Releases a neutrino (takes away energy and momentum)
Gamma Decay
Has no mass or charge (it’s a wave)
Decays to give out energy
Neutrinos
Conserves energy in beta decays
Has no charge and almost no mass
1930 - Wolfgang Pauli found the neutrino
1955 - Neutrino was observed
Atomic Structure
A Na Z
A = p + n (nucleon number)
Z = p = e (proton number)
Isotopes
Same proton number, different nucleon number
Same number of protons, different number of neutrons
Specific Charge
Specific Charge (C/kg) = Charge (C) / Mass (kg)
Proton Charge and Mass
p+
- 6x10-19 C
- 67x10-27 kg
Neutron Charge and Mass
n
0 C
1.67x10-27 kg
Electron Charge and Mass
e-
- 1.6x10-19 C
9. 11x10-31 kg
Photons Equations
EM radiation exists as photons
Energy (J) = Planck’s Constant (Js) x Frequency (Hz)
Energy (J) = Planck’s Constant (Js) x Speed (m/s) / Wavelength (m)
Proton and Antiproton Rest Energy
938MeV
Neutron and Antineutron Rest Energy
939MeV
Electron and Positron Rest Energy
0.511MeV
Neutrino and Antineutrino Rest Energy
0MeV
J to eV and eV to J
J to eV - divide by 1.6x10-19
eV to J - multiply by 1.6x10-19
eV is the work done when an electron moves through a pd of 1V