Breaking a glass using an electromagnetic wave

[eoghan]

Hi there!
I was wondering: is it possible to break a glass using an electromagnetic wave at its resonant frequency?

 

[pallidin]

Well, I've heard of using resonant sound frequencies to "break a glass"
Not sure about resonant EMF.

 

[Danger]

At first read, I thought it extremely unlikely. EM covers an awful lot of bandwidth, though. Perhaps if the frequency of EM falls within a range that the glass absorbs rather than passing or reflecting, it could work. I don't know enough about it to give a reliable opinion.

 

[mrspeedybob]

An EM wave of high enough intensity and at a frequency that the glass absorbs, if dirrected at one part of the glass but not at another will cause uneven heating. This will translate into uneven expansion which can cause cause the glass to break.

 

[eoghan]

Uhm.. do you know the resonant frequency of a crystal?

 

[Danger]

Uhm.. do you know the resonant frequency of a crystal?

I don't think that you can actually determine that other than experimentally. As far as I know, all crystal stemware, ornaments, et al are made of lead crystal. The amount of lead present varies, so it seems to me that the resonance frequency would as well. Also, the specific shape probably makes a difference.

 

[Phrak]

Glass is a dielectric, so in principle this should be possible, but would require a substantial amount of power. It would be far easier to electrostatically drive the fundamental frequency of a glass with a thin, even transparent conductive coating.

 

[NobodySpecial]

Non-resonant is fairly easy

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