Nuclear Physics Flashcards
J.J. Thompson model name
Plum pudding model
After Thompson model
Rutherford scattering experiment
After Rutherford scattering experiment
Bohr’s model which led to our current nuclear model
Why is the nuclear model a model
Because we don’t know what the atom looks like but we know the effects that it causes
Isotopes
Are 2 or more atoms that have the same number of protons and electrons /relative atomic number but different numbers of neutrons/relative mass numbers.
Characteristics of alpha radiation are
Low penetration
High ionisation
Can be stopped by a few centimetres of air or by a sheet of paper
Used in smoke detectors
Indicated by the breakdown of an atom into a different atom of a different element alongside with a helium nucleus being produced.
Occurs generally in heavier elements
Characteristics of beta radiation
Medium penetration
Medium ionising power
Used in paper thickness gauge - if it’s too thick not enough beta particles get through
A beta particle can either be a positron or an electron
Indicated by the breakdown of an atom into a different atom of a different element where a neutron becomes a proton and a fast moving beta particle is ejected from the newly formed atom.
Occurs generally in lighter elements
Characteristics of gamma radiation
High energy/ high frequency EM wave
High penetration
Low ionising power
Can be reduced by lead and concrete but not stopped
Used as a medical tracer, in radiotherapy such as gamma knife surgery
Gamma radiation gets rid off spare energy hence happens in all atom decays
The decay constant indicates
The probability that a nucleus will decay in the next second measured in per seconds
