Surface Tension: Calculation & Unit Conversion

AI Thread Summary
The discussion centers on calculating surface tension and its unit conversion in a physics assignment related to temperature. The formula used for surface tension involves density, radius, height, and gravity, with initial measurements in various units. Participants suggest converting all measurements to consistent units, specifically cm and g/cm², to derive the correct unit for surface tension, which should be dynes/cm. There is clarification that surface tension is defined as force per unit length, not torque. The conversation concludes with a positive note about hoping for a good grade on the assignment.
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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.

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

f=MLT^{-2}
Hence surface tension=ML^2T^{-2}

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
 
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