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Homework Help: Fission chain reaction

  1. Jul 4, 2008 #1
    The fission reaction n + 235U → 236U* → 141Ba + 92Kr + 3n produced 170 MeV of kinetic
    energy.

    A. How many of these fission events are needed to produce energy of 1 kilowatt- hour (kWh), that is, the energy it takes to run your blow dryer for an hour?

    B. How many neutrons are produced in this chain reaction process?

    I know how to do A. I was just wondering how to do part B. Is it just: 3^(# of reactions needed)?
     
  2. jcsd
  3. Jul 5, 2008 #2

    CompuChip

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    Why do you want to exponentiate that?
    And are you sure that in the end, you have 3 neutrons left for each reaction?
     
  4. Jul 5, 2008 #3

    dynamicsolo

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    For part B, you need to give the net change in the number of free neutrons.
     
  5. Jul 5, 2008 #4

    CompuChip

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    If you don't see why it shouldn't be 3, take a look at dynamicsolo's signature :smile:
     
  6. Jul 5, 2008 #5
    Thanks guys!
     
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