Here's some data, a regression model based on a large data set of actual comfort surveys in different conditions. The results are summarized in figure 8, where you see that the highest temperature considered comfortable is dramatically affected by humidity, but the effect on the coldest temperature considered comfortable is tiny, and perhaps not statistically significant.

This is all indoors, however, whereas I think the question is more focused on outdoors. It's worth noting that the temperature considered there is the operative temperature including the effect of the mean radiant temperature as well as the air temperature.

I'm not sure exactly what your question is, but once you have reached boiling, leaving it sitting there boiling does not change the temperature of the water, which is already at 100° C. So all the energy that you are using while you are leaving it sitting there boiling is being wasted, except to the extent that it's useful in heating the house and, if you need added humidity, humidifying it.

What would be relevant here is the convection coefficient, which is a result of heat capacity, thermal conductivity, and viscosity, as well as the geometry and the wind, if any. But it doesn't change significantly with humidity at cool or cold temperatures.

I think a better (but still sloppy and qualitative) analogy is that if the marbles bouncing around hit a layer of stationary marbles held together with pudding, and they knock loose some more marbles when they hit, that process will absorb use up some of their kinetic energy.

Yes, the effect of humidity on insulation is a very real effect, perhaps better documented for building insulation then for clothing, although it's well known among outdoors enthusiasts that cotton loses its insulation value rapidly when it's wet to the point of being soggy. Of course, that's complicated by the fact that the local environment between the shell of your outer layer and your skin might have different humidity than the outdoor air, especially when you first step outside and form the impression of how cold it feels.

When you are wet is a little different from the air having high humidity. If you are wet, evaporative cooling has an impact, and if your clothes are wet, their insulation capability is degraded.

>Moist air is a better conductor than dry air, so moist cold air feels colder.

There are two problems with this explanation.

1. If we are talking about temperatures below about 50 F or 10 C, the amount of water vapor in the air, even at 100% humidity, is very small, a fraction of a percent, and so the impact it can have on heat transfer is very low.

2. According to this analysis, the impact, which is only about 3% at 50 F, is in the other direction: higher heat transfer with dry air. Perhaps that is not the best high quality source, so I would be open to revising this point if people have better sources.

I think we still need someone to come and provide a better explanation for the common perception that a cold day feels colder when the humidity is high. There may be other correlations. For example, it may be that dry, cold days often have more solar radiation, making surfaces around you warmer as well as warm and you directly, so you feel warmer because of heat transfer by radiation even while the heat transfer by convection is very similar to what it would be on a wet day. And on a wet day, the wet ground may be cooled by evaporation, making that difference even bigger. I hope someone can cite a study that includes that affect—the mean radiant temperature.

However, at 40 F = 4.4 C, 100% relative humidity means only 0.5% of the air is water vapor, so its impact on the heat capacity of the air is negligible.

There isn't a direct analogy, but if we zoom way out and describe cavitation as a nonlinear effect that occurs when the amplitude of a disturbance gets too big (in the case of cavitation to large a magnitude of negative pressure relative to the pressure at rest), there are certainly nonlinear effects that occur when the amplitude of an electromagnetic wave is too large. Principally, dielectric breakdown which includes arcing in air and breakdown of solid insulators as well. Electromagnetic design for high power operation often includes avoiding dielectric breakdown, similar to how fluid designs often need to avoid cavitation.

That's often in high voltage transmission lines and other equipment for the power grid, but most of that design is quasi-static rather than being explicitly in the domain of wave effects. But in high power radio transmitters, the need for good impedance matching at each end of a line going from, for example, a transmitter at the base of the tower to an antenna at the top, is directly linked to the need to avoid standing wave effects that lead to high electric fields and dielectric breakdown. The effect is quantified by the standing wave ratio (SWR), which, when it's high, means that the peak electric field is higher than it needs to be by that factor.

The description of the origin of color from a physics and physiology perspective is helpful and accurate. I would urge caution about drawing firm conclusions from that. That does not mean that no plants evolved to reflect wavelengths that appear to animals as vivid colors. It seems to be the case for trees that the colors are a side effect of what they are really doing, but that is not a conclusion that applies to all plant colors and cannot be proven by the physics and physiology of color.

Note that for a piston to sit securely in a cylinder without tipping, it has to be sufficiently long compared to the diameter of the cylinder. If you start making huge diameter pistons, you'll need them to be long, too. The volume of the piston would become huge, and it would be heavy and expensive. And hard to fit where you need it.

That might mean that you'd want many moderate size pistons instead of one giant one to lift a house. You could pipe them all the the same pump, and you wouldn't need any extra pressure because of the many pistons connected, assuming they are plumbed in parallel. You'd just need many pump strokes to move them a significant distance.

An example of electron temperature being different in a more common, familiar technology is a fluorescent lamp in which the electron temperature is much higher than the gas temperature. That's part of the explanation of how it can efficiently produce UV to then excite the phosphor.

I call it a common, familiar technology, but it is rapidly on the way out now that LEDs offer better performance at low cost.