Recent content by Allen Montgomery

I was making these markings by hand, although I used a short cup so I could look at it and mark it from the side. But yes it was a bit awkward but I did get mostly consistent results in the experiment The base of the tube was resting on the base of the cup for every trial as well.

No there were two marks on the capillary tube itself, one for the depth (roughly 2.7cm) and one for total height (4.6, cm on average). The difference between these values should be the h values in the capillary equation.

No there was not, I simply held the tube with my hand and marked the depth and total height with a marker.

I did check but the height was always measured in cm for my raw data then converted to m later on. I will take another look.

I can certainly say that I tried to hold the tube as upright in the experiment but I may have not been that precise with the angle of contact.

I see what you mean, I used new plastic cups for each trial but I will have to evaluate my experiment in the near future. But besides that are there any mathematical errors that could be of an issue?

I used a new capillary tube for every trial so that would eliminate the detergent residue (it was a variable I discussed in my paper). On the jar of tubes, it read 0.9mm-0.5mm, which I assumed that .5mm referred to the hole and .9mm as the total diameter. Could that be an issue? I will double...

Ok, that great, and I did accidentally write m/s when it was supposed to be m/s^2. Any idea on what could have caused my value (.02359 kg/m^s) to be so far off from .073-0.74 N/m that it should be? That is the biggest issue I am having to deal with. (Also estimated the value for Surface...

And by the way, I think the value you quote is for 70C, not 70F. Thank you haruspex, you are correct the reference site I used was in F, after some conversion my value should be around .073-.074 N/m range. I did make the necessary conversion for my density which did solve my issue concerning...

I will have to take a look at that in my calculations, I clearly missed that. I'll post my new results when I get a chance. Thank you for the help, sir!

I am supposed to be using SI units, did I miss a conversion?

Should be g/ml

I am unsure as to what you are referring to, do you mean the radius of the hole? In that case it is m

Homework Statement Hello everyone, I am doing an experiment and I've hit a snag with my calculations. I am looking at how concentrations of soap affect surface tension in water. I am have been using the capillary equation and capillary tubes for my calculations. I have practiced this method for...