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I EMFs, what energy comes off items? How to explain?

  1. Nov 1, 2016 #1
    Hello,

    I do have an question about electromagnetic fields (EMF).

    Yesterday I conducted an small experiment after stumbling onto videos on YouTube about EMFs and the alteration of human biology. Those stunned me, because I had no idea electromagnetic fields could alter human physiology. On further investigation, I found a website listing outcomes of scientifical studies done upon EMFs, radio frequencies and so on.

    While reading the summaries of those studies, I remembered that everytime I had to plug in my stereo-speakers into my computer's audio jack, there was a buzzing sound coming of them. So with my fingers I touched the metal connector of the cable and the buzzing sound started.

    Well, I am of curious nature. Connecting the idea of amplifying electromagnetic fields (EMFs) - or at least I think the sound represents EMFs - I conducted myself to objects around me while still being connected to the audio device.

    * When touching my computer, the sound got quite louder and the frequency changed.

    * When touching my tablet computer, the sound got a bit louder and the frequency changed.

    Now up to here I could explain this (for me) phenomenom:
    My body picks up the electromagnetic field and changes it's vibration towards the more powerful field available, which seems to be the electromagnetic ones on direct contact.



    But then my explanation attempts came to an end, when I discovered the following:

    * When touching the side of my fridge, the sound got extremely louder

    * When touching the front of my oven, the sound got a bit louder

    * When touching the metal frame of my cooking ceramic glass cooktop, the sound got extremely louder

    * When touching radiator (central heating), the sound got extremely louder

    * When touching the plant next to me, the sound got a bit louder

    (All of the above changed sound frequency also)


    So how does one explain this? I am quite lost in searching for answers, because I do not know the scientifical / technical terms at the moment.
     
  2. jcsd
  3. Nov 1, 2016 #2

    Drakkith

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    Staff: Mentor

    First, be very, very careful with what you take in from youtube videos. A huge number of them are entirely false or have twisted the truth so far that it loses almost all meaning.

    Kind of. I believe your body acted like an antenna and helped transmit the EM field generated by your electronic devices into the speakers. The frequency likely remained the same as the source.

    I'm not an electronics expert, but I'm betting all of those items can have an induced EMF in them which can be transmitted through touch to your speakers. Large appliances like your fridge likely have unshielded electronic components that directly generate an EMF. That's probably why those objects made the loudest buzz when you touched them.
     
  4. Nov 1, 2016 #3
    Thank you very much Drakkith for your answer.

    So to clarify:
    The speaker cable acts as an antenna itself, but when I do connect my body to the antenna cable, my body becomes an even more powerful antenna, which then picks up electromagnetic fields and sends them through the wire into the speaker?

    I still do not understand the EMF itself, so I will do some follow-up reading.

    The most suspicious effect when I touched my radiator stunned me the most. Can it be possible that the heating system is under electrical influence? How can I find out what kind of energy is emmited?
     
  5. Nov 1, 2016 #4

    Drakkith

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    I think so. I'm really not an expert in this area, so I hope someone can elaborate a bit more on this.

    Well, it's metal, so it likely does a good job of picking up all those radio waves bouncing around everywhere, along with any nearby low-frequency EM fields such as the ones that are emitted from transformers and other devices.

    As for what kind of energy is emitted, it's simply going to be electrical or electromagnetic energy (both kinds of energy are transferred through the EM field). But that's really not that important. I expect you aren't familiar with how energy is actually defined and used in science, so can you elaborate on what you'd like to know when you ask what kind of energy is emitted? Also, I'm a bit tired and about to go to bed, so I may not respond for a while. Hopefully someone can help you between now and then.
     
  6. Nov 1, 2016 #5
    Yes you are right, I am not very confident in my knowledge about energy. Way back in school I learned about energy types, electric energy, electromagnetic energy and so on. I guess, although I did not have bad grades at all, I still do not understand the functioning.

    Well when I ask about the kind of energy, my thought process is like this:

    The radiator must emit some kind of energy because I can here it buzzing on the speaker. Now it could be electrical energy conducted through various sources. Maybe it is the central heating unit which emmits electricity onto the pipes. Maybe the heating system is "grounded" and picks up electrical energy from the grounding system. Maybe the radiator itself emmits a kind of energy that is produced by heating up the metal (very unlikely though).

    Let's say the radiator bears access to another grand antenna, which is the heating system itself. Now you said that metal is very able to pick up electromagnetic fields (makes sense, antennas are made of metal because of that).
    Also, I rule out the EMF I find on the radiator is generated by the heating process itself.
    And then I narrow my observations by saying the speaker system is only able to emmit sound near 50 - 60 Hz.

    So the electrical field in / on the radiator must be near 50 - 60 Hz, which is the usual electrical energy frequency used.

    How can I measure my observations and can I measure more variables like voltage and current?

    How am I able to find out where the heating system picks up the energy?
     
  7. Nov 7, 2016 #6

    BvU

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    Boy, this thread is only a week old and I just bumped into something you might want to look at: ground loops
     
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