Water as a dielectric. Is this video a good demonstration?

[HelloCthulhu]

I found, at least in my uneducated opinion, a very good demonstration of water as a dielectric. I understand that putting water in a bag will change the dielectric constant of the water in it somewhat, but I think the capacitance meter at least makes water's value as a dielectric visually quantifiable. In the video, the ziplock bag of water increases the capacitance of the capacitor by a factor of 100.



Over a week ago, I posted a homework question I theorized regarding the breakdown voltage of water. But due to electrolysis in the capacitor, the calculations were deemed inconclusive. Could I use this scenario as a basis for hypothesizing the behavior of water as a dielectric? Any thoughts on this are greatly appreciated.

https://www.physicsforums.com/threa...air-and-water-capacitors.939151/#post-5940147

 

[Ygggdrasil]

The dielectric constant of water at room temperature is ~ 80, which is fairly close to the value you report from your experiment: https://en.wikipedia.org/wiki/Relative_permittivity

 

[phinds]

Could I use this scenario as a basis for hypothesizing the behavior of water as a dielectric?

Why would you think otherwise? As ygggdrasil said, and as the guy in the video said, water has a dialectic constant of about 80 and air is 1.

 

[HelloCthulhu]

Why would you think otherwise? As ygggdrasil said, and as the guy in the video said, water has a dialectic constant of about 80 and air is 1.

Just making sure! I'll repost the equations I was working on in the chem homework thread. I hope I get it right this time.

 

[sophiecentaur]

regarding the breakdown voltage of water.

High purity water is a pretty good insulator with a high breakdown voltage. High power Radio Valves have water cooled Anodes and they have EHT voltages of tens of kV.