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Larry Morries

01:17

Anyone can tell me if I can post this question into electronics.stackexchange.com - What tools are used to protect one from electrical magnetic field when operating on devices that is use to DIY something or on something that one is DIY on it? (Asked in Home Improvement and they asked if I have consider posting it in electronics.stackexchange.com.)

Also, would appreciate if I can also post this question - Are Aluminum wire mesh better than Aluminum foil in protecting a person from electrical magnetic field?

Lastly, also this question - The induction process in a induction cooker is consider as a process of transfer of heat (convection, conduction and radiation). So, is induction more of a process of which transfer : convection, conduction or radiation?

Would appreciate if anyone can tell me which forum to post if I cannot post it in electronics.stackexchange.com. Thanks.

13 hours later…

Kevin Vermeer

14:40

@LarryMorries Both this question and the aluminum wire mesh/aluminum foil question assume that there is a need to protect from electromagnetic fields without describing the fields. I suspect that you are not an electrical engineer, if you were, you would have described the frequency and power of the EMI to be blocked.

@Kortuk has some experience working with high-power electromagnetic fields that would cause tissue damage, but your questions (coupled with the induction cooker question) seem to indicate that your motivation is not about electronics design, but rather about fear of electromagnetic fields. We'd much prefer questions about electronics design, but we allow a very few questions like this. Your fears may be alleviated by this question:

Q: Frequency ranges that causes a hazard to humans

I hope many people might feel little awkward to see this question. But I feel this is important. Because in my place where I am living I can get a radio (Audio Receiver) very cheaply. I don't know till what extent they allow the audio frequency ranges. I guess they use ICs for Frequency Demodula...

If not, then please do more research so that you can ask an informed question. You may find that your resulting question is about challenging a claim; that would be better suited for Skeptics. It might be about the physics behind electromagnetic waves and their effects on human bodies, that would probably be better suited for Physics. Finally, it may be about designing a device that shields workers from dangerously powerful electromagnetic fields, that would be welcome here.

@LarryMorries You state:

> The induction process in a induction cooker is consider as a process of transfer of heat (convection, conduction and radiation).

and then ask which of these mechanisms is in place.

This is a false dillema. The process is not a transfer of heat, it's a transfer of energy in the form of electromagnetic radiation to the cookware, where it is absorbed and transformed into heat energy.

In a similar fashion, solar (light) energy is transformed into electrical energy by a solar cell - there's no conduction circuit between the sun and the solar cell. Alternatively, in a gas stove, chemical energy in the gas is transformed into heat energy in the flame - there's no conduction, convection, or radiation of the heat/solar energy absorbed long ago by the plants which decomposed into the gas directly to the flame.

Check out this wikipedia article:

Energy transformation

Transforming energy is when the energy changes into another form. In physics, the term energy describes the capacity to produce changes within a system, without regard to limitations in transformation imposed by entropy. Changes in total energy of systems can only be accomplished by adding or subtracting energy from them, as energy is a quantity which is conserved, according to the first law of thermodynamics. According to special relativity, changes in the energy of systems will also coincide with changes in the system's mass, and the total amount of mass of a system is a measure of its...

for more information. If you're interested in designing an induction heater, feel free to ask here. If you're interested in the process of energy transformation from one state to another, that would be a question for Physics.

8 hours later…