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Penetrating Ability.
The ability of radioactivity to pass
through materials
is called its penetrating
ability.
It depends on the size of the
radioactive particle.
The table of the summary of
properties shows that a-particles are the biggest,
b-particles are very
much smaller and g-rays have
no mass.
The bigger the particle,
the more likely it is to collide with the atoms of the material.
The collision will stop the particle
going through the material.
a-particles are the
biggest and are least able to
penetrate a material.
Paper will stop them and even in
air a-particles only
travel
for a few centimetres before they are stopped.
b-particles are stopped by a few millimetres of aluminium.
g-rays are the
most able to penetrate
and will even find their way through metres of concrete.
When the particle or ray
collides with the material
it can knock an electron off the atom
and form an ion.
Penetrating ability is related to ionising ability.
The one which is least able to penetrate is
the most likely to cause
ions.
Headings Radioactivity Search
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Copyright © 2008 Dr. Colin France. All Rights Reserved.