C. What is the average energy released per fission event in this chain reaction?

AI Thread Summary
The fission reaction of uranium-235 produces 170 MeV of kinetic energy per event. To determine the number of fission events required to generate 1 kilowatt-hour (kWh) of energy, calculations can be performed based on this energy output. The discussion also addresses the number of neutrons produced in the chain reaction, with a clarification that the net change in free neutrons should be considered rather than simply exponentiating the number of reactions. It is emphasized that each fission event produces three neutrons, but the net count must account for any neutrons consumed in subsequent reactions. Understanding these dynamics is crucial for accurate calculations in nuclear fission processes.
pooka
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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)?
 
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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?
 
For part B, you need to give the net change in the number of free neutrons.
 
If you don't see why it shouldn't be 3, take a look at dynamicsolo's signature :smile:
 
Thanks guys!
 

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