[Top] [All Lists]

Re: [TowerTalk] Soil resistivity test done: Some questions

To: <>
Subject: Re: [TowerTalk] Soil resistivity test done: Some questions
From: "David Robbins K1TTT" <>
Date: Sat, 9 Sep 2006 19:49:17 -0000
List-post: <>
Actually ohm-m or ohm-cm is correct, a couple definitions that make it

resistivity-(Also called specific resistance.) The electrical resistance per
unit length and per unit reciprocal cross-sectional area of a given material
at a specified temperature. 
It is also possible to define the resistivity of a substance as the
resistance of a cube of that substance having edges of unit length, with the
understanding that the current flows normal to opposite faces and is
distributed uniformly over them. Resistivity is commonly expressed in units
of ohm centimeters. The reciprocal of resistivity is conductivity.

Resistivity - an intrinsic property of a material determining the materials
resistance to the flow of current. Resistance in ohms is equal to the
resistivity of the material multiplied by the cross sectional area of the
material divided by the length of the material. Resistivity is frequently
used to specify electrically active doping level and also as a measure of
the ionic content of water.

David Robbins K1TTT
AR-Cluster node: 145.69MHz or telnet://

> -----Original Message-----
> From: [mailto:towertalk-
>] On Behalf Of K8RI on TowerTalk
> Sent: Saturday, September 09, 2006 19:34
> To:;
> Subject: Re: [TowerTalk] Soil resistivity test done: Some questions
> > 'Resistivity' or 'Resistance'??  I am confused by the wording of some of
> > your measurements... and since you don't give units I have to assume
> > certain
> > things.  Note that 'resistance' is measured in ohms, 'resistivity' is in
> > ohm-meters, or occasionally ohms-cm.
> Other than a nit...resistivity would be ohms per cubic CM, or cubic meter.
> In electronics we used cm^3 but I'd guess in the electricall transmission
> area it'd be m^3
> Roger Halstead (K8RI and ARRL 40 year Life Member)
> N833R - World's oldest Debonair CD-2
> (Use return address from home page)
> _______________________________________________
> _______________________________________________
> TowerTalk mailing list


TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>