Chronology | Current Month | Current Thread | Current Date |
[Year List] [Month List (current year)] | [Date Index] [Thread Index] | [Thread Prev] [Thread Next] | [Date Prev] [Date Next] |
The time dependence of a population of decaying atoms is assumed to follow
the Poisson law
N(t) =N(0)e^{-pt).
the half-lkife T' is defined to follow N(T') =N(0)/2, or
e^{-pT'} =1/2
Taking the ln of each side of the last equation gives:
pT' =ln2, which leads immediately to the quoted equation.
On Sat, 18 Apr 2009, Brian Whatcott wrote:
John Denker wrote:
On 04/17/2009 10:25 PM, Hugh Haskell wrote:We?
we know that half-life (T) can beWhat do you mean by "we", Kemosabe?
expressed as
T = (ln 2)/p (1)
The folks at MIT giving an introduction to modeling radio-active
half-life, for example.
See this version
<http://www-math.mit.edu/~djk/calculus_beginners/chapter12/section02.html>
Hugh is in fact illustrating a comparable example to the difference
between compounding capital at time intervals, say weekly, monthly,
quarterly etc., and
compounding capital continuously. This is a standard introductory
element of
teaching exponential versus discrete time models, I thought?
Brian W
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l