Re: inverse square law - limitations?

["ruth_weiner" <ruth_weiner@email.msn.com>]

The inverse square law  (transmitted radiant energy is inversely
proportional to the square of the distance between the receptor and the
source) applies when the radiation moves in straight lines (in an unimpeded
path) and when the source is spherically symmetric and at a long distance
from the receptor.  The universal gravitational law is an inverse square
law:
Gm1m2/r^2.  The shorter the distance between source and receptor, the less
the inverse dependence.  Closer to the source, the dependence becomes
proportional to 1/r, and very close, the energy field is uniform (we on the
earth's surface experience gravity as a uniform field.

Ruth Weiner
ruth_weiner@msn.com
-----Original Message-----
From: P van Rooyen <rooyen@aib-vincotte.nl>
To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
Date: Wednesday, August 16, 2000 11:18 PM
Subject: inverse square law - limitations?


>Dear radsafers,
>
>The dose rate at a certain distance from a point source can be calculated
>with the 'ambient dose rate constant H*10' for that nuclide and the inverse
>square formulae.  This is an approximation as I understand based on the
>difference in area, where the 4-pi is included in the constant.
>



************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html