Re: Expressing fractions

From: Paul J Kriha (paul.nospam.kriha_at_paradise.net.nz)
Date: 01/06/05 

Date: Thu, 6 Jan 2005 20:10:02 +1300

Lee Sau Dan <danlee@informatik.uni-freiburg.de> wrote in message
news:871xczhoot.fsf@informatik.uni-freiburg.de...
>>>>> "Paul" == Paul J Kriha <paul.nospam.kriha@paradise.net.nz> writes:

    Paul> What's more, there is a reason why your ohmmeter will give
    Paul> you misleading resistance figures. Resistance of the
    Paul> metal-hand contact is _voltage_ dependent!!! Your ohmmeter
    Paul> performs the measurement in wrong condition. I guess it has
    Paul> an internal batery of 1.2/1.5V.

This problem can be overcome by using zero-current methods of
measuring resistance. I don't know if those cheap electronic
multimeters use any current when in resistance measurement modes.
Anyone knows?

<my answer>
What a suprise! You don't understand the nature of the *problem*
but you know how to overcome it.

The reason why we want to know the resistance of the human
body is to be able to calculate if a deadly level of current
will flow through it when certain voltage is applied.

Because most of the resistance is usually in the body-conductor
contacts and that part of resistance is heavily voltage dependent,
any measurements at low or zero voltages give totally misleading
figures.

When deadly voltage is applied the resistance barriers in the
contact areas brake through and the actual circuit resistance is
an order or orders of magnitude lower than what you may have
measured with any low voltage method.

Paul JK
<end of my answer>

Lee Sau Dan

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