Four-Point Resistance Measurement? | When and Why, Yo? | Doc Physics

[@Tracing0029]

I sincerely thank you, some uni professors have a hard time explaining something like this in a straightforward manner.

[@billwilliams6338]

DOC SCHUSTER, can you give examples of when you would use the 4 wire kelvin measurement for testing boards or troubleshooting circuit boards for what kinds of stages or sections in a circuit?

[@mimimeviracrochet]

what is the explanation if i make a 4 wire measurement but the input is voltage, not current...

[@thesila2000]

What is the difference between voltage and field in a current

[@rosensofroniev1264]

Very all over the place explanation. I knew how 4pp works and still I found the flow of you explanation confusing. Can only imagine what it would be like for someone being introduced to the topic.

[@mollyzhu2848]

Can I use the device Agilent 4155C and use the method of four-point to measure the resistance, and the size of my sample is really small.

[@Taran72]

Great Video (as all of the other ones)! I find it useful not only for students but also for professionals like me. A lot better then going back and reading about it. I knew about the voltage thermal effects of the current probes and the losses in the test leads, but missed that in the mass I need to see the probes as a "3D" current source and the potential lines are not exactly parallel near the probes. So my question is: how far should the voltage probes be from the current probes so that we are measuring in the "parallel potential lines" region? And thank you for pointing out the "Squishy Circuits" I will buy it :)

[@DocSchuster]

You could measure the curve of the potential lines directly with your voltmeter and then decide how straight you need them to be. I'm sure their curvature depends on the permittivity of the material and the dimensions of the material, also!

[@Taran72]

Thanks!

[@Taran72]

Maybe the ASTM standards recommends placing the potential leads at 1.5 times the perimeter of the cross section perimeter of the specimen from the current leads so that were measuring in the "parallel potential lines" region? Also in that region the potential and current is uniform throughout the specimen.

[@DocSchuster]

Wow - yeah! That's a neat specification, of which I was not aware. Makes tons of sense!

[@StefanConstantinDumitrache]

bloop bloop ha ha ha who the hell is this guy :D

[@chaudry123]

Resistivity is independent of the dimentions

[@shafagh_projects]

excellent. thank you so much

[@chaudry123]

No matter you take 1km or 1mm of a material its resistivity will have the same value🤔

[@wadupboi4423]

Resistivity depends only on the nature of the material, not on its dimensions, but this video talks about RESISTANCE which definitely depends on both the resistivity of the material and its dimensions.

[@kylekim7848]

god thks understood!!