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Effect of water flow on electrical resistance

  1. Apr 9, 2009 #1
    I have been investigating the effect the flow rate of water has on the electrical resistance of the water. My hypothesis is that the faster the water flow rate the lower the electrical resistance.

    I have tested this using a fairly basic rig to regulate different flow rates and a multimeter and so far my results have supported the hypothesis.

    Problem is I cannot really fathom why. I originally thought that the drop in resistance could be explained by the water moving the electricity faster between the two points, but this doesn’t really explain the large drop in resistance I am recording.
    Any insights into this would be really helpful, I am finding it hard to continue the investigation without a reasonable explanation.

  2. jcsd
  3. Apr 9, 2009 #2
    Although there may be no direct effect of the flow rate of water on the resistance of water, the resistance of water can have an effect on the flow rate. If water has a resistance, like ocean water, then if you flow a current I through ithe water, and have a large magnetic field B orthogonal to the current, then there will be a force (propulsion) perpendicular to both the current and magnetic field. This is the Lorentz force F = I x B. Google "magnetohydrodynamic propulsion" for information,
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