# Half life time

1. Apr 6, 2015

### skrat

1. The problem statement, all variables and given/known data
Nucleus $^{252}_{98}Cf$ alpha decays with half life time $t_{1/2}=2.6$ years.
What is the velocity of the alpha particle after the decay?
Estimate the half life time of the nucleus after the decay.

2. Relevant equations

3. The attempt at a solution
Ok, no worries about the first part. I think i understand it and I think I got it right. My result is $v_\alpha =0.058c$.

However, I have got absolutely no idea what to do with the second part, where I am supposed to estimate the half life time of $^{248}_{96}X$.

I was thinking about Geiger-Nutall law, but I think this wouldn't be OK, even if I could somehow determine the constants in the equation. Any ideas on how to start here?

2. Apr 6, 2015

### SteamKing

Staff Emeritus
I don't know why you are writing the daughter element as $^{248}_{96}X$. Can't you find a periodic table and look up element 96?

3. Apr 6, 2015

### skrat

Because:
- I won't have a periodic table on the test either so I won't be able to look up for element $96$ (or any other that is not already stored in my head).
- It doesn't change anything.