Soap bubble measures electric field

[Loren Booda]

Can one determine a local electric field by the change in interference spectrum of a soap bubble? If one notes the spectrum with E=0, then applies a nonzero E-field, would the effect of the induced repulsive charge on iridescence be relatively easy to calculate, given the additional variable of local surface tension?

 

[gabee]

Mmm...I'm not sure that would be very easy, since the turbulence of the colors in the bubble are so random already, and depend on things like surrounding air currents, currents within the bubble, and so on...and it would probably be very hard to quantify any such change even if it is visible.

Interesting idea though!

 

[3trQN]

I don't see why not in principle, wouldn't it be similar to crystallographic methods?

 

[3trQN]

Mmm...I'm not sure that would be very easy, since the turbulence of the colors in the bubble are so random already, and depend on things like surrounding air currents, currents within the bubble, and so on...and it would probably be very hard to quantify any such change even if it is visible.

Interesting idea though!

I don't think its so difficult to isolate a single bubble and study it in controlled conditions, using already available techniques. I think temp variations would present the biggest difficulties. I am not very familiar with the details of X-Ray Crystallography though, but its a topic that I am very interested in at present.

 

[gabee]

It would probably be a lot harder than X-ray crystallography, since the molecules in a soap bubble are not crystallized and static; rather, they move around a lot. I would guess that when an electric field is applied, the polar water molecules would tend to line up somewhat with the field, but the effect wouldn't be visible since the thickness of the water and soap films would still be about the same as with no field. Of course, I could be completely wrong. If you can, try this out!