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Homework Help: Radiation Dose Calculation

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  1. Dec 22, 2017 #21
    Thank you.

    Can anyone else please type out their worked solution? This type of question might come up in my exam and I still don't understand how to do it. I need to know how to do it step by step.
     
  2. Dec 22, 2017 #22

    kuruman

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    Sorry, forum rules expressly prohibit what you ask. You will find them here if you have not already seen them.
    https://www.physicsforums.com/threads/guidelines-for-students-and-helpers.686781/
    Under item 8:
    "Complete solutions can be provided to a questioner after the questioner has arrived at a correct solution. If the questioner has not produced a correct solution, complete solutions are not permitted, whether or not an attempt has been made."

    Read post #20 by @gleem and see if you can reproduce the numbers show.
     
  3. Dec 28, 2017 #23
    Hi PSR, why is 84 divided by GBq in the first line? Is it a given value in a text book?
     
  4. Dec 28, 2017 #24
    Could you tell me the website / book which gives the specific dose rate (84sv/h/GBq). Thank you
     
  5. Dec 28, 2017 #25
    See my post 15
    "The dose for Cs137 is due to the 662 keV
    You know that H=1.5E-10×A×i×E (in mSv/h) with A in Bq , E in MeV and i=.85 See, for example chapter 4 of
    http://www.springer.com/us/book/9783319486581 "
    84 microSv/h/GBq means 84 microSv/h for 1 GBq at one meter
     
  6. Dec 29, 2017 #26
  7. Dec 29, 2017 #27

    kuruman

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    First you need to convert 662 keV to MeV in the format 6.62×10y MeV. (What should y be?). Then you find the closest value in the Table and interpolate.
    Be sure to read how to use the value that you found here.
    https://physics.nist.gov/PhysRefData/XrayMassCoef/chap2.html
     
  8. Dec 29, 2017 #28
    For 6.62x10-1 the closest value is 6.00000E-01, which gives a reading of 1.248E-01 for u/p. Not sure what to do now.
     
  9. Dec 30, 2017 #29
    Right so 6.00000E-01 cm2g-1 x 11.34 gcm-3 gives ~ 1.4 cm-1 for u. When I put all of this into my formula I get 28.98cm which is apporoximately 30cm. I'm satisfied that this is the correct answer unless anyone thinks my value of u is incorrect?
     
  10. Dec 30, 2017 #30
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