# Homework Help: Easy question?

1. May 12, 2005

During the fission of an atom of uranium-235, 200 Mev are released. If the average time between generations of fission reaction is 10e-14 seconds and if each fission reaction gives rise to two fissions in the next generation, calculate the time required to go from the first fission to 100 Kw output.

200mev=200000000ev=0.000,000,000,032jouls per sec
1kw=1000joules
31250000000000reactions per second to make 1kw
now my thinking was (long version) 1x2 till i reached 3125000000000000 and took how many x2s it took to reach 3125000000000000 and x taht by 10e-14 but taht didnt work any help is appreaciated
i know its easy (or it should be) i just cant figure it out at the moment

Last edited: May 12, 2005
2. May 12, 2005

perhaps this question is harder than i think for the great minds that roam these fourms cannot direct me in the correct direction

3. May 12, 2005

i formula perhaps? maybe a hint like what number it starts with? anything? no? sigh...

4. May 13, 2005

wow no one could help me with this question?

5. May 13, 2005

### OlderDan

All those zeros are too scary for most of us to deal with. Your approach is basically correct, but it would be easy to miscount the number of generations. How many x2s do you think it takes?

Do you know about logarithms and exponentials?

6. May 13, 2005