Measuring underwater electricity

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Discussion Overview

The discussion revolves around measuring the current in water using a fish tank setup with batteries and an ammeter. Participants explore the relationship between the circuit current and the current in the water, considering factors such as resistance and geometry.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions whether the current registered by the ammeter is the same as the current in the water, expressing uncertainty.
  • Another participant asserts that the fish tank would carry the circuit current, noting that the resistance depends on contaminants in the water and the geometry of the probe tips.
  • A third participant reiterates the initial question and concludes that since the fish tank is in series with the circuit, all circuit current must travel through the water, thus affirming it is the same current.
  • A later reply challenges the practicality of using a fish tank of the specified dimensions, questioning the setup's feasibility.

Areas of Agreement / Disagreement

There is some agreement that the current in the water is the same as the circuit current, but the discussion includes uncertainty regarding the factors affecting this relationship, such as water resistance and setup practicality.

Contextual Notes

Participants mention the dependence of resistance on water contaminants and probe geometry, which may affect the current measurement but do not resolve these factors.

Kramjit
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Suppose I connect 2 9v batteries (for example) in series with a fish tank (30mm x 30mm x 20mm) containing water and an ammeter, is the current registered the same as the current in the water? I should think so but I am not sure.

The copper wires-cum-electrode being positioned at either ends.

Much thanks
 
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Yes, the fish tank would carry the circuit current. The resistance of the tank would be dependent on the contaminates in the water and the geometry of your probe tips.
 
Kramjit said:
Suppose I connect 2 9v batteries (for example) in series with a fish tank (30mm x 30mm x 20mm) containing water and an ammeter, is the current registered the same as the current in the water? I should think so but I am not sure.

The copper wires-cum-electrode being positioned at either ends.

Much thanks

Because the fish tank is in series with the circuit, all the circuit current must travel through the water. So yes, it is the same current.
 
Surely you don't have a 30mm x 30mm x 20mm fish tank. What are you doing?
 

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