Question about waves, maybe diffraction related

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Monochromatic waves can pass through apertures smaller than their wavelength, contrary to initial intuition. When the aperture is smaller than the wavelength, maximum diffraction occurs, causing the central bright fringe to dominate the screen. This principle explains why radio waves can penetrate buildings despite their long wavelengths. The discussion emphasizes the importance of wavelength over amplitude in wave behavior. Understanding these concepts clarifies misconceptions about wave interactions with small openings.
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I don't know why my intuition tells me that generally if a monochromatic wave goes toward an aperture smaller than its wavelength (or half its wavelength maybe), the wave can't go through the aperture. Is it true?
I don't think so now... I see no reason why it would be true. And we couldn't listen to radio inside any building...
I'd like a confirmation, thank you.
 
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Remember, it's the wavelength, not the amplitude of the light wave...
If the aperture is smaller than the wavelength, there would be maximum diffraction - the central bright fringe would fill the entire screen!
 
tan99 said:
Remember, it's the wavelength, not the amplitude of the light wave...
If the aperture is smaller than the wavelength, there would be maximum diffraction - the central bright fringe would fill the entire screen!

Hmm? I never wrote "amplitude" and I did use "wavelength".
So you're saying that if I send a radio wave (for example wavelength around 10 km) through a 500 nm width slit, the wave would pass through the slit?
 
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