Atoms and nuclei
For just over a hundred years, physicists have been building models of the inside of atoms. Understanding and explaining atomic and nuclear structures in terms of fundamental particles remains one of the challenges of modern physics.
Since the late 1800s, there have been ever more ingenious experiments whose results inform the developing models. Some of the experiments can be carried out in a school laboratory. They are safe, lively activities that can take students into a new world of physics – beyond the macroscopic.
There is a real sense of wonder in seeing the path of beta particles change when they pass through a magnetic field, and realising that even these invisible particles obey known laws of physics by moving according to Fleming’s left hand motor rule.
Through the experiments in this topic, students can develop their own ideas of what is inside an atom. This will give them a feel for what it is like to be a real physicist – using models of the invisible to explain observed effects.
Ionising the air
Counting ions and ionisation
Ionising radiations and their properties
Exponential decay and half life
Model of the atom
Electron beams (cathode rays)
From electrons to electronics
Properties of the electron
Managing radioactive materials in schools
Radioactive sources: isotopes and availability
Nature of ionising radiations
First models of the atom
Developing a model of the atom: radioactive atoms
Evidence for the hollow atom
The great scattering experiments
Alpha particles as tools
Exponential decay of a radioactive substance
Light behaving like a particle
Electrons behaving as waves
Putting together a scheme of work