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ArcticMyst Security by Avery

In for a surprise: the resistance of water

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If you're absolutely lifeless like me, try measuring the resistance of tap water...





































Too lazy? Here, let me do it for you:
dsc8644.jpg


And a video too:

Sorry about the background noise. It's the loud Vibration Reduction feature on my Nikon lens. Absolutely not meant to record videos.

Is it only with my multimeter? Just curious. :D
 





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Your video does not show you testing water...
The DMM probes are on the table...:thinking:

The resistance of water depends on the amount
and type of impurities suspended in it.


Jerry

You can contact us at any time on our Website: J.BAUER Electronics
 
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Blord

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100% H2O shouldn't conduct any electricity. It is the minerals and impurities in the water that causes the conductivity.
 
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Your video does not show you testing water...
The DMM probes are on the table...:thinking:

The resistance of water depends on the amount
and type of impurities suspended in it.


Jerry

You can contact us at any time on our Website: J.BAUER Electronics


Sorry, the video isn't crystal clear. The probes are actually in a sink with water in it. Unfortunately my camera can't auto focus, hence the blurry video.
(Same setup as the picture.)

100% H2O shouldn't conduct any electricity. It is the minerals and impurities in the water that causes the conductivity.

That's true, but negative ohms? :wtf:
 
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Try a bowl of water instead. The drain plug can pick up EMI that might throw off your readings.
 
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Try a bowl of water instead. The drain plug can pick up EMI that might throw off your readings.

Yup, at first I thought the same thing, but got the same result:

dsc8646o.jpg


The value starts off at 0.022 ish ohms and then drops below zero... :confused:

Can anyone duplicate these results?
 

benmwv

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My best guess is that the metal probes and contaminants in the water have produced a primitive battery.
 

Blord

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Nope, my value always stays positive. Your Fluke need a fix. :D

IMG_6561.JPG
 

ARG

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1.5M ohms where I am (We have mineral heavy water)
 
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What no one has made an impromptu resistor for a custom antenna out of a small container salt and water? Visine bottles and ear plug cases work well. They add salts to water in to help soften it and whatnot, after it rains, my tap tastes like dirt, some of the sediment is conductive in water and it settles or out gasses as it sits, and a DMM shows the the change from conductive less conductive as the impurities settle or rise.
 
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What no one has made an impromptu resistor for a custom antenna out of a small container salt and water?

Not only is that large and likely to spill/leak, it will degrade the electrodes as you pass a current through it. Resistors are stable, small, and cheap.
 

Fiddy

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get some distilled water!

at work we run distilled water through high voltage busbars and inside induction coils to cool them down, we have conductance meters that measure the waters conductance (Si unit S, the Siemens) S= 1/Ω more particular the meters are in uS, so the water is a pretty good insulator for electrical arcing and tracking.
 
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Not only is that large and likely to spill/leak, it will degrade the electrodes as you pass a current through it. Resistors are stable, small, and cheap.

It all depends, I can honestly say I have had to use that method and I did get it to work. I hit a station 60 miles away on a 16 mile radio by making a field expedient long wire. Hard to find a radio shack in the middle of no where. The electrolyte solution will not spill or leak unless you make it do so but it will very slowly evaporate changing your resistance. Yes its temporary and not the best option, but its a well used field expedient method of making a temporary resister.
 
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its a well used field expedient method of making a temporary resister.

Well used by whom? People that have no idea what they're doing, perhaps. There's no excuse for not having a kit for these things if you're working in the field; they're practically free, and take up almost no space.

Besides, if you're resourceful enough to find salt, water, electrodes, and a container, you're resourceful enough to find a better solution (no pun intended). There are countless other materials that are better suited for the task than salt water.
 
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LOL at people who have no idea what they are doing, I was a commo guy 11 years and a avionics tech for 6 I have no clue what I am doing. I got it to work, I could make it work over and over again, just think of it as a survival technique, and not every one carries resistors in their pocket. There is no need to be spiteful try it if you do not believe me. The publication that lists the tables for sodium chloride to water ratio is the Rangers Handbook. I know your the absolute expert and all so just take what I say with a grain of...salt.:beer:
 
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