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Help with syringe pressure and Students T test

  1. May 7, 2007 #1
    I am a doctor with limited mathematics knowledge. I am trying to prove to my medical fraternity that for a given force of aspiration, a smaller syringe generates a higher "negative pressure". I did a small experiment. I hung an one kilogram weight on a 5 ml and 10 ml syringe and connected it to a Digitron electronic manometer. I got the following neg pressure readings (cm Hg).
    The 5 ml syringe: 57.3;55.8;56.7;56.6;55.9;56.6;57.4;56.1;56.1;56.6 The 10 ml syringe gave the following: 32.8;32.3;30.7;31.9;31.9;32.6;30.6;33.3;32.1;30.5
    I would like to"scientifically" say that the smaller syringe creates a bigger negative pressure.
    Would a "Students t" test be an appropriate one to use ? Can I use MS excel do do the test ?

    With regards to the posting by light_bulb: for each reading , i gave a 30 second time period for the readings to settle. Hopefully that will look after the time aspect of things ?
    Last edited: May 7, 2007
  2. jcsd
  3. May 7, 2007 #2
    you'll be using more force in the same amount of time to compensate for filling more volume, so unless your juggling the amount of force or time the larger syringe will create a higher negative pressure.

    i'd just put it down like ml / seconds * 0.19336779 = psi a second at 0 degrees c
    Last edited: May 7, 2007
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