John Cuthber

If I remember correctly, the finesse of a Fabry Perot resonator depends on how good the mirrors are. If the mirrors are reflective enough then the theoretical bandwidth will fall below the limits imposed by the vibration of the resonator. Setting aside the theoretical engineering limits of an infinitely stiff or massive system, and the practical problem of shutting the lid fast enough, I still wonder what happens to the spread of frequencies of photons in the box (now defined as having "arbitrarily good" mirrors) over time. Does energy get "randomly" coupled from one photon to another, and if so what does the distribution look like in the long run? It seems to me to be analogous to the redistribution of energies between molecules of a gas (not the same- they hit don't each other directly) so I wonder if they end up looking something like a Boltzmann distribution or a black body one.

No, not if you are prepared to wait. Even energetically disfavoured reactions happen (slightly).

I'm still not convinced you need a resonance. In particular, the vibrations will never go away- there will always be zero point vibrations. Those will "doppler shift" the photons a bit as they bounce back and to. I wonder if, in the end, you get a distribution of photon energies that looks like black body radiation. Also, since the initial pulse was finite, the energy, and hence wavelength, of the light is uncertain so the box can't be a "perfect" match to it. If it makes you feel better please assume that the mirrors are sufficiently massive that the effect of photon impact is "small" on a particular timescale- say 3 score years and ten. Then increase the mass and see what happens to the outcome.

Cooking must be interesting in your house. Rather than take the lid off a pan to put stuff in, you try to force it through the lid. I'm assuming the box is big enough that I can open it, flash a light in and then close it before the light bounces back out again. And we all know that perfect mirrors don't actually exist. That's not the point. So, where does the light go?

Are ruled out, because they are perfect mirrors. " reflection at the input." What "input"

Sometimes, but sometimes not "The electromagnetic fields around power lines have the ability to concentrate radon, and may also concentrate other harmful substances into a potent cocktail of carcinogens."

You described it as healthy- I presumed you were being ironic, rather than meaningless. A transposition error Nope, not even 1 If you think that something made from aluminium 11 mm thick can be rolled up into rolls 125 feet long and 4 feet wide (but with the rolls weighing 21 pounds then- lets just say you are not on this planet. The thickness is specified as 11 mil- which is heavy duty for cooking for cooking foil, but not nigh half an inch as you suggested. https://www.ebay.com/p/Nashua-Aluminum-Foil-Tape-for-Waterproofing-Repair-48-Mm-Width-11-Mil-Thick/682240054?iid=322854283848 This is the sort of stuff that's 11 mil thick

What do you mean by intelligent?

I can see how a high voltage cable could attract dust carrying radon daughters. I can't see how it's meant to attract an inert gas. It's either BS or poor reporting (or both).

It seems there's some confusion about digestion and metabolism. For example, aspirin isn't a useful drug. However it is metabolised in the body to form salicylic acid which is a painkiller. Digestion refers to the processes that happen in the gut and it usually refers to food degradation. Most metabolism takes place in the liver (though it can happen anywhere in the body). Drugs don't (often) work before they are digested because, at that point they are still in the gut lumen somewhere.

1/c

"Some large studies, including a large study in the United States, have failed to find any link between living near power lines and developing any sickness or diseases, such as cancer. A 1997 study found that it did not matter how close one was to a power line or a sub-station, there was no increased risk of cancer or illness." from https://en.wikipedia.org/wiki/Electric_power_transmission#Health_concerns

What do you consider "straw man" to mean?

Where does it go?

I'm a broad band emitter- and a broad band absorbed too. So, to me, it doesn't matter much if I'm "irradiated" by 200µW of narrow or broad band radiation. It won't do me any harm. I never checked the RF attenuation of a layer of foil. 50Bd might be a cautious value (or even a guess). 99.999% will convince most people it works. This page which cites over 100 dB reductions might be just as valid. http://www.slt.co/products/RFShieldingFoil/RFShieldingFoil.aspx The "phone in a wrapper is probably the best "measurement" I could do

The Tory govt came in with a promise to axe public services, and they did it. They are currently working to destabilise the NHS. They are, unequivocally a Right wing government. On the other hand, they have done quite a good job of portraying themselves as "moderates" and MrCorbyn as "loony Left".

"As it's not easy, if possible, to weld cooking foil, I assumed you meant wrap the source in cooking foil, which would leave gaps and enough leakage to detect the source at significant distance." Overlapping the joints + crimping them would work fine. If this is right http://www.spectralcalc.com/blackbody_calculator/blackbody.php then I think I emmit more than 200 µw of microwave radiation. It may be instructive to wrap your mobile phone in foil carefully, then try to call it. A bit of bubble wrap round the 'phone first might be a good idea.

Dilute solutions of bicarb might not be alkaline enough to affect phenolphthalein. Methyl orange might be a better bet. Make sure you do a trial run first or the kids would get a valuable lesson in the fallibility of teachers. Universal indicator might be interesting- it may give an idea of "how badly infected" someone got.

If you wrap your head in foil you will verify that it gets dark.

Hold a sheet of foil up to the light from the sun. Can you see through it? The eye will detect light over a range of something like 12 orders of magnitude. If you can't see through the foil it's attenuation must be (at least) something like 1,000,000,000,000 fold. Do you agree with my assessment that it is "for all practical purposes" opaque? It's much more difficult to do the experiment at other wavelengths because we can't sense them directly.

Actually, one of the numbers is a consequence of the definition of the ampere. "The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed one metre apart in vacuum, would produce between these conductors a force equal to 2×10−7newtons per metre of length." Which requires that the magnetic permeability is, by definition exactly 4 x pi x 10^-7 Henries per metre.

For many years, phenolphthalein was used medicinally as a laxative. It was taken off the market because there's a suspicion that it caused cancer in some animal studies. However, many millions of people swallowed it regularly over a period of many years and the doctors never noticed any raised cancer risk. So, if one of your class drinks the phenolphthalein they will regret it, but it is unlikely to do them any long term harm. The other indicators are also generally not very toxic. However if you want to remove the risk of being "accused" of putting the kids at risk. http://www.bbc.co.uk/schools/teachers/bang/videos/lesson1_red_cabbage_indicator.shtml Another thing to consider; do any of the local schools support your club? They might donate a little universal indicator.

F=M g The force F on an object of mass M is given by the product of the mass and the local value for the acceleration due to gravity g. So a mass of 1 Kg has a weight of about 9.8N

Interference isn't a loss mechanism. The dark fringes are dark, but the bright fringes are brighter, to make up for it. Also, nobody said the box was an integer number of half wavelengths or whatever. It's not a requirement that the wavelengths "fit"

America lost track of the political middle ground some years ago. They only have a Right party and a Further Right party.