2 - Particles & Radiation Flashcards
Specific charge
Charge (C) / Mass (Kg)
- charge is calculated: number of protons x charge of one
- mass is calculated: number of nucleons x mass of one
Strong force
An attractive force that is greater than the repulsion between protons in the nucleus (keeps atom stable)
Range: 0.3-3fm distance it is attractive, highest stability at 1.2fm
Before 0.3 it is repulsive, after 3 it is 0
Electrostatic repulsion
Always repulsive but when strong force is greater it is overall attractive
Much larger range
Nuclear stability
When forces are balanced, reasons for instability:
- too many neutrons/nucleons
- too few neutrons
- too much energu
Alpha Emission & Radiation
A helium nucleus, 4He (2+)
Radiation has constant energy values, energy and momentum are conserved
Decay: atom loses 4 nucleons, 2 protons + He
Beta Minus Emission & Radiation
β particle (an electron), makes a neutron turn into a proton
Radiation: continuous spectrum of energies and velocities
- an antineutrino is emitted in beta decay to make up for any KE not accounted for
Neutrinos & Anti
No charge, no mass, range of energy
A neutrino is antimatter, matter is antineutrino
00V: neutrino
V/: antineutrino
Beta Plus Decay
Emission of a β+ particle = a posterior (antiparticle of electron)
Same mass but opposite charge
A neutrino is emitted
Beta Plus Decay
Emission of a β+ particle = a posterior (antiparticle of electron)
Same mass but opposite charge
A neutrino is emitted
Gamma Radiation
Energy emitted from a nucleus with too much energy
No change in nucleon numbers
Cloud Chamber Experiment
the greater the ionisation, the thicker the tracks (heavier and slower)
uncharged particles leave no charge
in the presence of a magnetic field, charges
