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stvoffutt
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Homework Statement
A 2 [itex]\mu[/itex]g sample of [itex]{}^{47}Ca[/itex] is encased in a lead sphere. What is the photon intensity 5 cm from the source? Use some of the tables in your book to find the required information.
Homework Equations
Flux/Intensity of photons from a point source:
[itex]\phi(r)=\frac{S_p}{4\pi r^2} e^{-\mu r} [/itex]
Where [itex]\mu[/itex] is the total microscopic cross section, r is the radius(distance) from point source and [itex]S_p[/itex] is the particles per unit time.
The Attempt at a Solution
I can and have done these problems when the energy of the sample is given. However I have never done one where the weight of the sample is given. I am lost on this problem. My main question here is: How can I go from weight to photons/second?
I tried calculating [itex]S_p[/itex] by using 1047.1 keV/decay listed in the textbook but I still don't know where to go from there. Ci:=decays/second. How many photons per keV?? Or am I over thinking this?