4 ms·

Heating of water is a bulk thermal effect. Absolutely nothing happens when you microwave a glass of water that wouldn't also happen if you heated it on the sto

Heating of water is a bulk thermal effect. Absolutely nothing happens when you microwave a glass of water that wouldn't also happen if you heated it on the stove, or put it under a heat lamp. Only the spatial distribution of the heat is different. I'm assuming that your last sentence is merely snark, or perhaps you didn't finish reading my post in its entirety. I already have too many books on EM physics written by people who are actually familiar with the subject that I don't have time to read or understand. Uninformed online posts end up being skimmed, for better or worse.

carbocation 16y ago
I already have too many books on EM physics written by people who are actually familiar with the subject Good, perhaps you can explain yourself in more detail, then, because your post seems quite wrong to me and I would like what I assume to be my misunderstanding to be corrected. Absolutely nothing happens when you microwave a glass of water that wouldn't also happen if you heated it on the stove, or put it under a heat lamp. I was always under the impression that your stove heated via conduction (e.g., the transfer of heat from molecules on the stove to molecules in the pan holding your water to molecules of water). I was also under the impression that microwaves heated water via a dielectric effect (i.e., the water molecules interacting with the microwaves directly and heating up due to their 'attempts' to align with the rapidly-oscillating field + friction). Finally, I was under the impression that heat lamps heated things via radiative (e.g., infrared) heating. Radiative, conductive, and dielectric heating can all warm up the right substance. But I cannot agree that "absolutely nothing [different] happens" since their mechanisms are quite distinct. Please tell me why this is incorrect. Now, once you deposit the thermal energy into the water by one of the three methods listed above, I think we can all agree that convection will cause it to dissipate in the same fashion, regardless of how you got it there.
- pbhjpbhj 16y ago
  >>Absolutely nothing happens when you microwave a glass of water that wouldn't also happen if you heated it on the stove, or put it under a heat lamp. I'd like to see someone superheat water on the stove or indeed boil water inside a block of ice under a heat lamp.
  - CamperBob 16y ago
    Yeah. Superheating. That's what must be causing all these new cases of cancer that have appeared since people began using hand-held cellular phones in the late 1980s. /rolls eyes
    - pbhjpbhj 16y ago
      >>Absolutely nothing happens when you microwave a glass of water that wouldn't also happen [...] You can roll your eyes all you like it won't make that true. The parent made a general statement for which I believe there to be clear factual objection which I mentioned. The only logical contradiction would be to show the falsehood of such objection. I did consider saying "obviously this isn't the mechanism here" but I think the take-away is that you shouldn't make universal statements that are obviously false. This does actually then have a bearing on the matter in hand. If the universal is false then it opens the path for other unknown mechanisms to be considered that may also contradict such a universal statement. If people are willing to make such demonstrably false claims at such a low level then trusting them to clearly and accurately present the more complex situations becomes extremely difficult [for me]. Perhaps I'm unique in this but if you lie to me about one thing then I'm disinclined to believe you about another.
- CamperBob 16y ago
  At this point, of course, you've moved the goalposts to the thermal side of the field. Are we talking about 'teaching the controversy' of athermal effects, or of thermal ones? ... Radiative, conductive, and dielectric heating can all warm up the right substance. But I cannot agree that "absolutely nothing [different] happens" since their mechanisms are quite distinct. Please tell me why this is incorrect. The mechanisms are not the least bit distinct at the molecular level. In each of these cases, heating occurs by simple friction. It comes down to the difference between a chemical change and a physical change. Microwaving the water, shining a light on it, or cooking it on a stove burner will cause physical changes. Ionizing radiation causes chemical changes. The distinction between these two types of effects isn't just important, it's the only one that matters.

carbocation 16y ago

I already have too many books on EM physics written by people who are actually familiar with the subject Good, perhaps you can explain yourself in more detail, then, because your post seems quite wrong to me and I would like what I assume to be my misunderstanding to be corrected. Absolutely nothing happens when you microwave a glass of water that wouldn't also happen if you heated it on the stove, or put it under a heat lamp. I was always under the impression that your stove heated via conduction (e.g., the transfer of heat from molecules on the stove to molecules in the pan holding your water to molecules of water). I was also under the impression that microwaves heated water via a dielectric effect (i.e., the water molecules interacting with the microwaves directly and heating up due to their 'attempts' to align with the rapidly-oscillating field + friction). Finally, I was under the impression that heat lamps heated things via radiative (e.g., infrared) heating. Radiative, conductive, and dielectric heating can all warm up the right substance. But I cannot agree that "absolutely nothing [different] happens" since their mechanisms are quite distinct. Please tell me why this is incorrect. Now, once you deposit the thermal energy into the water by one of the three methods listed above, I think we can all agree that convection will cause it to dissipate in the same fashion, regardless of how you got it there.

pbhjpbhj 16y ago
>>Absolutely nothing happens when you microwave a glass of water that wouldn't also happen if you heated it on the stove, or put it under a heat lamp. I'd like to see someone superheat water on the stove or indeed boil water inside a block of ice under a heat lamp.
- CamperBob 16y ago
  Yeah. Superheating. That's what must be causing all these new cases of cancer that have appeared since people began using hand-held cellular phones in the late 1980s. /rolls eyes
  - pbhjpbhj 16y ago
    >>Absolutely nothing happens when you microwave a glass of water that wouldn't also happen [...] You can roll your eyes all you like it won't make that true. The parent made a general statement for which I believe there to be clear factual objection which I mentioned. The only logical contradiction would be to show the falsehood of such objection. I did consider saying "obviously this isn't the mechanism here" but I think the take-away is that you shouldn't make universal statements that are obviously false. This does actually then have a bearing on the matter in hand. If the universal is false then it opens the path for other unknown mechanisms to be considered that may also contradict such a universal statement. If people are willing to make such demonstrably false claims at such a low level then trusting them to clearly and accurately present the more complex situations becomes extremely difficult [for me]. Perhaps I'm unique in this but if you lie to me about one thing then I'm disinclined to believe you about another.
CamperBob 16y ago
At this point, of course, you've moved the goalposts to the thermal side of the field. Are we talking about 'teaching the controversy' of athermal effects, or of thermal ones? ... Radiative, conductive, and dielectric heating can all warm up the right substance. But I cannot agree that "absolutely nothing [different] happens" since their mechanisms are quite distinct. Please tell me why this is incorrect. The mechanisms are not the least bit distinct at the molecular level. In each of these cases, heating occurs by simple friction. It comes down to the difference between a chemical change and a physical change. Microwaving the water, shining a light on it, or cooking it on a stove burner will cause physical changes. Ionizing radiation causes chemical changes. The distinction between these two types of effects isn't just important, it's the only one that matters.