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A2 Module  5 Nuclear Instability

This A2 module builds on the ideas introduced in Module 1. Students will gain knowledge and understanding of the present-day views of the particle nature of matter.
14.1.1 Radioactivity a,b and c radiation; their properties and experimental identification;  applications, e.g. to relative hazards of exposure to humans
The experimental investigation of the inverse square law for c rays 

I =k Io

Applications, e.g. to safe handling of radioactive sources
Background radiation; its origins and experimental elimination from calculations

14.1.2 Exponential law of decay Random nature of decay

DN = lN     N = No e -lt

Half-life and decay constant and their determination from graphical decay data

T1/2 = ln2

Applications, e.g. relevance to storage of waste radioactive materials; radioactive dating

14.1.3 Variation of N with Z for stable and unstable nuclei Graph of N against Z for stable and unstable nuclei
14.1.4 Possible modes of decay of unstable nuclei a, b+, b-, nucleon emission, electron capture

Changes of Z and A caused by decay and representation in simple decay equations

14.1.5 Existence of nuclear excited states c ray emission.  
Application, e.g. use of technetium–99m as a gamma source in
medical diagnosis
14.1.6 Probing matter Scattering as a means of probing matter, including a qualitative discussion of the choice of bombarding radiation or particle, the physical principles involved in the scattering process, the processing and interpretation of data
14.1.7 Nuclear radius Estimation of radius from closest approach of alpha particles and determination of radius from electron diffraction; knowledge of typical values.
Dependence of radius on nucleon number.
R = R0 A 1/3
derived from experimental data

Northallerton College web site

Freeserve stuff on nuclear physics