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siddharth5129
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Here's a thought experiment : Two identical spherical waves exactly 180 degrees out of phase destructively interfere throughout all of space. Is the energy contained in them just lost ?
siddharth5129 said:Isn't it even theoretically possible to set up two identical spherical waves to destructively interfere throughout all of space?
siddharth5129 said:Here's a thought experiment : Two identical spherical waves exactly 180 degrees out of phase destructively interfere throughout all of space. Is the energy contained in them just lost ?
I nearly always like to look at this sort of problem in terms of RF antennae; the situation is more concrete and practical when approached that way. Also, you don't have to worry about coherence, if you use the same driver oscillator.Malverin said:Destructive interference through all space is possible only if the two sources are at the same place and with same frequency, but with 180 degrees phase shift.
It is not possible, that sources are at exactly the same place in space. So there will never be full destructive interference.
Image.
http://www.cyberphysics.co.uk/topics/light/A_level/interference.htm
sophiecentaur said:A practical / thought experiment: When you try to place two or more antennae near each other and feed them with the same signal (which is what you are implying) and try to adjust the phase to produce a null (or low level field strength in 'all' directions, you find that they affect each other and the impedance you need to drive them with gets lower and lower. This causes progressively more and more power loss in your driving source. You can get a narrow beam, channelling most of the power into a small range of directions, which is basically limited by the spacing ('aperture'). You can do a bit better than this with a 'super gain' array, in which the individual elements (of a multiple element array) have very high currents in them and are driven in near-opposite phases but it's a law of diminishing returns and, as with the two batteries, you end up chucking more and more power away in your power sources.
The Energy Conservation Law still rules, so relax.
It is not just practically impossible, it is impossible even in theory. Poynting's theorem follows directly from Maxwell's equations and the Lorentz force law:siddharth5129 said:I get that it's practically impossible to set up two spherical waves to destructively interfere throughout all of space. But if somehow you could do it, would you have violated energy conservation?
Energy conservation refers to the principle that energy cannot be created or destroyed, but can only be transformed from one form to another.
In the case of identical destructive interference, energy conservation means that the total energy of the system before and after the interference remains constant. This is because the energy is simply redistributed or cancelled out, rather than being lost or created.
Energy conservation is important because it helps to sustain the balance and stability of natural systems, and it also has economic and environmental benefits. By conserving energy, we can reduce our reliance on non-renewable resources and decrease our carbon footprint.
No, energy conservation cannot be violated in identical destructive interference. It is a fundamental law of physics that has been extensively tested and proven to hold true in all situations.
We can utilize energy conservation in our daily lives by being mindful of our energy consumption and making small changes, such as turning off lights and unplugging electronics when not in use. We can also choose energy-efficient appliances and use renewable energy sources when possible.