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Capillary Action- Rate/Temp- How would you analyze?

  1. Jan 27, 2007 #1
    Hi Folks -

    This started out as a simple experiment we could do for my daughter's science fair (9th grade). Now I am truly ashamed to admit that I don't really know the best way to analyze the reasonably good results of the experiment.

    The experiment was to measure the effect of fluid temperature on capillary action in paper. We set up a frame to hold strips of paper in tension, suspended so they weren't touching the frame where the fluid wicked up the paper. The ends of the strips were dipped in the water to some consistent "zero" point and the height of the fluid was measured at regular time intervals. We measured this at room temperature, and the water bath was (1) room temp, (2) ice water, and (3) heated to an initial temperature of 98C, but cooled to about 54C over the course of the experiment. Note that I tried to get my daughter to do a better job with the hot experiment, but she was lazy and stubborn, so be it.

    We experimented with about 8 different types of paper (itself an interesting experiment) and finally selected one particular paper napkin that gave a slow enough rate to be measurable easily at regular time intervals and was fast enough that each experiment could be concluded in 30 minutes.

    The results were actually more dramatic than anticipated. I posted them here:
    height vs time for three fluid temperatures:

    (sorry, you'll have to cut and paste, as they won't let a newbie post a link!)

    I've got some ideas how to analyze this, but have been frustrated as to how rusty my skills have become. And so I kindly ask: How would you analyze this experiment?

    - Many thanks in advance.
  2. jcsd
  3. Jan 27, 2007 #2


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    http://en.wikipedia.org/wiki/Viscosity" [Broken]

    Last edited by a moderator: May 2, 2017
  4. Feb 22, 2007 #3
    well yeah lower viscosity is more fluidity thus faster motion, but do they teach viscosity to 9th graders? another explanation would be that Pressure is P= Rho*g*h, Rho being the density of liquid, g is the gravitational constant, and h is the height reached by the liquid. since ur experiment is close to a barometer i think it measures the ambient pressure, and since Rho lessens with heat, h has to increase so that the pressure remains constant, but i think you need to verify this idea
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