Why sound can be heard on the other side of a brick wall, but light couldn’t be seen regardless of intensity?
In: Physics
So, both hearing through a wall and seeing light through a wall would involve energy transfer.
When you’re hearing through a wall the energy of the sound transfers to the wall and makes it vibrate, transmitting the sounds
For light to do this it would have to be so powerful and hot on one side that the energy transfers into the wall and transmits light – so intensity does matter
Sound is a pressure wave – molecules hitting eachother in succession like one of those clacky-ball desk toys. They can clack their way through the molecules in a brick too, but a lot of energy is lost when you try to clack from brick back into air.
Light is a different kind of “wave” that is carried by its own particle. Those particles can be deflected or absorbed by matter and the silicates in bricks are very good at blocking visible light. Some low energy photons are better at evading the absorbing power of bricks and will penetrate a brick wall, but your eye can’t detect them.
Your cell phone can though.
Sound is a vibration. If that vibration touches something, the thing it touches will also vibrate. This is why sound can be heard through solid objects.
Light is a particle, called a photon. Photons are really really small, but the gaps in a brick wall are still too small for the photons to go through, no matter how many you throw at them. This is why you can’t see through a brick wall.
If the light was intense enough it would penetrate through, but sound is a wave and it transfers its energy through the wall I’m not sure about lights wave particle duality but I bet that has something to do with it, sorry for only answering half the question
Sound moves air. Air moves wall. Light does not move air. It bounces off wall. An intense enough light would pass through at some point due to photons bouncing off of individual pores in the brick.
Sound waves can vibrate the things they hit. So even though a brick wall may seem immovable, it can in fact be vibrated by sound. This however means that much of the sound waves energy will be absorbed by the wall, given how dense it is. It’s also worth mentioning that the deeper the sound, the longer its wave length and the higher chance it has of being heard through walls, as longer wave lengths lose less energy when encountering obstacles.
Visible light cannot penetrate a brick wall as it will absorb or reflect all of the lights energy. Radio waves on the other hand can go through brick walls as they have a much longer wave length and do not give up as much energy when encountering brick walls. FYI, radio waves and light are very similar, they exist on the same spectrum, just at different ends.
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