GCSE Physics

GCSE Physics

1. Term 1

   • Atomic structure
     • nucleus contains protons and neutrons
     • beta radiation
       • has a medium ionising power
     • alpha radiation
       • high ionising power
       • a thin sheet of paper will absorb alpha rays
       • the range of gamma radiation in air is 5 cm
       • alpha decay alters the parent nuclei by decreasing their atomic number by 2
     • gamma radiation- an electromagnetic wave
       • low ionising power
       • serveral mm of lead will absorb gamma rays
       • the range of gamma radiation is unlimited
     • radioactive decay is the unstable nucleus changing to become more stable and therefore giving out radiation
     • ionisation can cause cancer through mutating DNA
     • activity- the rate at which decay occurs
     • atoms have no charge
     • JJ Thompson came up with the plum pudding model
     • irradiation is when a product is exposed to radiation
     • radius of an atom is 0.1nm
     • half life- its is the time taken for a radioactive nuclei to half