MIT Physics Demo -- Microwave Interference

A double-horn microwave emitter faces a microwave receiver. The receiver is also connected to a speaker, which displays the received signal as audio, and an oscilloscope, which displays the signal visually. When the receiver is moved perpendicularly to the emitter, constructive and destructive interference can be both seen and heard.

When one of the emitter horns is covered, the interference pattern disappears.

See the original post on MIT TechTV - http://techtv.mit.edu/videos/632

Category:

Education

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• Mittechtv
• physics
• mit
• demo
• demonstration
• waves
• interference
• microwave
• transmit
• receive
• electromagnetism
• speaker
• sound

[KaslarProductions]

actually, sound + inverted sound = no sound.

[Bummer4yall]

Bummer, I was waiting to see hand start smoking.

[freethisone]

challange this just in. take for instance a vacume tube fill it with argon neon or what have you place inside a gap for electrisity to spark arcross after you aply energy from a microwave emmiter. is there any usable electrisity? now within the same vacume tube have intense UV light LED will for sevral, now you will have a tube that is condutive altoghther because of the UV light.

[ubuntututorials]

@wdowa94 The audio signal is probably modulated onto the microwave carrier, that's how it can be heard...

[wdowa94]

2.4 GHz?

[KaslarProductions]

@marsCubed Thank for the info.... I learn something everyday

[marsCubed]

@KaslarProductions Actually that is not true.

Although it is the case that one may cancel a signal to a speaker with an inverted wave form, in practice sound does not behave like that.

I worked with a sound engineer who told me that anti sound is Not used to cancel sound very often, basically if you pump a lot of energy into a sound system, adding anti sound adds energy too.. it leaks and can only make a small quiet zone, usually all that sound will be even louder somewhere near by.

[super6plx]

I'd love to see a perfectly generated 3D interactive picture of this wave interference effect (and by 3D I don't mean 3D animation of a 2D picture, but a three dimentional depiction of this effect)

[TheFaustschlag]

am ende sieht man heisenbergsche unschärferelation

[KaslarProductions]

yay triangle waves are awesome