Absorption of Beta and Alpha Radiation

R2: Absorption of Alpha and Beta Radiation
Aim
To investigate the absorption of beta and alpha particles through different absorbers.
Experimental Science (Physics)
By: Beta Squadron (Group 14)
Methods
Part A (Beta)
Part B (Alpha)
Measure background count rate
Measure average count rate and uncertainty w/o absorber in place
Find count rate for different absorber (lead, paper, polythene disk)
Measure count rate for different thickness of polythene disk (5-50 pieces)
Measure source-detector distance
Measure count rate for each shelf
Measure count rate w/o absorber and paper in place
Results
Part A (Beta)
Part B (Alpha)
Pattern and Analysis
Part A (Beta)
Part B (Alpha)
Real World Context
Part A (Beta)
Part B (Alpha)
Conclusion
Aim
of which to study the absorption of the alpha and beta radiation
has been achieved
.
The results obtained
supports
the expected relationship between the penetration of alpha and beta particles.
The percentage transmission of the penetration of
beta
particles is
higher
than
alpha
particles.
The method that have been used is
suitable
as it gives the results as expected.
Radon gas-scentless and colourless-cause over 21,000 deaths a year in the USA (EPA, 2013).
Natural gas by natural plutonium decay in soil.
From experiment, alpha particles are very weak (esp after 4 cm)
Solution: patching cracks- foundation of the home-alpha can't break through
Can't penetrate human skin etc. but, its a threat- contact with wounds, eyes, inhaled, digested.
Lead to CANCER
If patch not good enough, air filter can be used
From experiment, dense materials-best protection against beta radiation.
Polythene-best material-unlike lead (very dense but doesn’t cause secondary radiation- more deadly)
Beta-harder to exposed in real world (most are alpha).
More likely to be exposed-improper disposal of source.
Methods to store beta source- high precaution.
Eg:- Using barrels lined with a 8mm thick layer of polythene- eliminate any if not all threats, or maybe 10 mm
Variation in 3 0ne-minute count- electron that ejected
randomly
Count vs thickness satisfies linear regression (R-squared=0.9899)
Range- about 8mm of polythene
Number of radiation count > alpha
Range- about 4 cm in air
Alpha: beta penetration through paper= 99.54%:8.1%
Not easily penetrable
ionizing power>beta, so, penetrating power<beta.
Simple precaution needed
Penetration
: beta>alpha
Ionizing
: alpha>beta
Range
: beta>alpha
Precaution
: beta>alpha