8. A gamma radiation source (226Ra) is used in a hospital laboratory. If shielding is considered as a means of control, how many centimeters are needed to reduce the radiation to 1% of what a worker would be exposed to without shielding?
Assume the shielding material is (a) concrete, (b) steel and (c) lead. (Note: You will need to us the half-thicknesses of each material)
Concrete: Half thickness = 11.938cm
Steel: Half thickness = 1.778cm
Lead: Half thickness = 1.378cm
The radiation intensity reduced by the absorber is given by the following equation:
where m is the absorbtion koeffitient.
the half thickness k and ...
The radiation intensity reduced by the absorber is given by the following equation: I=Io*exp(-m*x)