Units for surface tension from capillary tube measurement

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shamstar
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i am doing a physics assignment on the realationship between surface tension and temperature. i have calculated the surface tension at various temperatures using a capillary tube and measuring the height. i was given the formula:
surface tension=(densityxradius of tubeheight of columnxgravity)/ 2
i have calculated the surface tension, however, I am not sure what units it is in. density was measured in g/mm^2, radius and height were measured in mm, gravity was measured in mm/s. I am not sure if the answer will be dyns/cm or ergs/cm^2? or even something else? thankyou
 
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shamstar said:
i am doing a physics assignment on the realationship between surface tension and temperature. i have calculated the surface tension at various temperatures using a capillary tube and measuring the height. i was given the formula:
surface tension=(densityxradius of tubeheight of columnxgravity)/ 2
i have calculated the surface tension, however, I am not sure what units it is in. density was measured in g/mm^2, radius and height were measured in mm, gravity was measured in mm/s. I am not sure if the answer will be dyns/cm or ergs/cm^2? or even something else? thankyou

First of all convert all the mm reading to cm. Also measure the density in gms per cm^2 and g as cm/s^2. Now you will get in dynes/cm.
 
surface tension=force*length.

[tex]f=MLT^{-2}[/tex]
Hence surface tension=[tex]ML^2T^{-2}[/tex]
 
chaoseverlasting said:
surface tension=force*length.

[tex]f=MLT^{-2}[/tex]
Hence surface tension=[tex]ML^2T^{-2}[/tex]

I think that you have made some mistake. Surface tension is force/length.It is torque which is force*length(radius). So surface tension would be ML^0T^-2
 
thanyou both so much. let's hope a get an A on my assignment! thanks again