Meassuring Resistance under water?

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The discussion focuses on measuring the resistance of a wire while it is heated underwater to establish a relationship between steady-state temperature and current. The proposed method involves using a four-point probe technique with insulated leads attached to the wire, submerged in distilled water. Participants confirm the approach is sound, noting a minor typo in the original post that mistakenly compared the resistance of water to itself instead of to the wire. The consensus is that the significant difference in resistance between the wire and the water should allow for accurate measurements. Overall, the method appears feasible for the intended experiment.
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Hey,

So as part of a experiment I am curious to be able to measure the resistance of a wire as I joule heat it under water to be able to get a steady state temp vs current. My thought is to attach electrodes to a metal wire to put a current across it and measure a voltage drop(4 point probe). I would likely use insulated leads attached to the wire that i want to measure. Additionally I would put the wire in distilled water when I make the measurements. So my thought is that since the resistance of the water is so much greater than that of the water I should be able to get a relatively accurate measurements. Does this make sense or am I missing something.

Thanks
Matt
 
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HappMatt said:
Hey,

So as part of a experiment I am curious to be able to measure the resistance of a wire as I joule heat it under water to be able to get a steady state temp vs current. My thought is to attach electrodes to a metal wire to put a current across it and measure a voltage drop(4 point probe). I would likely use insulated leads attached to the wire that i want to measure. Additionally I would put the wire in distilled water when I make the measurements. So my thought is that since the resistance of the water is so much greater than that of the water I should be able to get a relatively accurate measurements. Does this make sense or am I missing something.

Thanks
Matt

Makes perfect sense, except for the simple typo in your next to last sentence. You should be fine.
 
berkeman said:
Makes perfect sense, except for the simple typo in your next to last sentence. You should be fine.

sense instead of since? not the first time and I actually meant to type it that way.
Thanks
Matt
 
HappMatt said:
... So my thought is that since the resistance of the water is so much greater than that of the water I should be able to get a relatively accurate measurements...

Your typo was saying that you plan to compare the resistance of the water to the water (itself).
 
Yeah, change the 2nd water --> resistor.
 
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