Why is air a good insulator?
112334
Air is a good insulator as far as it doesn't circulate. It has low conductivity (about 1,4 Btu/ft h ºF), but if you let the air circulate there can be a very good heat transmission due to convection.\nThat's why insulators try to trap small amounts of air inside, so the air stays immobile.\nVaccumm would be a much better insulator.
334098
Hot air *can* contain more moisture than cold air, but it depends on how much moisture is available for it to contain.
929901
The evaporation from the ocean makes hot air.  Hot air moves creating charges.
1134163
I don't know of any specific studies about air conditioning.  However, I do know from experience that evaporative coolers promote the growth of mold and bacteria, due to the humidity they produce.  Mold and bacteria also can grow on the cooler itself.  Air conditioners, due to being more dry, inhibit the growth of mold and bacteria.  Air conditioning also helps keep out pollens and allergens from the outside air.  This can mean fewer lung and sinus infections for allergy and asthma sufferers.\n\nThat's not to say they're automatically more healthy.  Stale air isn't so good for us; we need fresh air circulating.  And, dry air means dry nasal passages and airways, which means they're in less-optimal condition to help us fight off cold, flu, and little infections we encounter.  So, depending on your local climate, and your allergy/asthma situation, air conditioning could be healthier, or it might not be.
561460
the ozone layer keeps the earth a stable temperature.
922061
An insulator is a material containing no electrical charges. When a voltage is sent across an insulator, no charges flow, so there is no electrical voltage\n\nGenerally,all non metals materials are good insulators.Such as plastic,glass,rubber(frying pot handle)
620837
Thermal insulation blocks the movement of heat.\n\nTypical thermal insulations are spun glass or fiber glass that traps air.  Trapped dead air is a very good insulator because it prevents convection transfer of heat.\n\nA vacuum is also a good insulator and that is how a thermos bottle works.\n\nStyrafoam is another excellent insulator.\n\nThe higher the R value on an insulating product, the more heat that it will block.\n\nConsider this temperature gradient and heat flow:\n\nOutside it is 5ºF.  Inside it is 70ºF.  Over the span of 4 to 6" in a normal wall, the temp gradient is 65 degrees!  What prevents all that heat from rushing outside?  Good insulation of R13-R19 in the wall.
1056436
Let me answer this way:  The static charge built up between the clouds and earth (ground) cause the air between to become ionized (lightening) causing a discharge of (usually) millions of amperes of current, neutralizing (minimizing) the charge.\n   And as you know, an efficient arrestor is designed to prevent any great voltage rise during the discharge.
717532
For academic related materials Wikepedia is the best in the business Go to http://en.wikepdia.org \nFor your quetion answer is already there on Wiki\nhttp://en.wikipedia.org/wiki/Electrical_insulators
748193
I think the reason for the insulator layer is obvious. The conductor layer is probably to shield against emission of electromagnetic energy which can interfere with communications (such as radio and TV reception) and other electronic equipment, and may also be a safety measure to produce a high fault current to trip a breaker in the event of cable damage.
604902
you get more air from the trees, it takes away carbon dioxide, and it protects the ozone from further damage.
119197
The system uses high voltage to ionize molecules in the air mostly oxygen to ozone. Ions have an electric charge sort of like static electricity they attract dust particles and create a heavier particle that falls out of the air. also dust particles are attracted to the high voltage plates much like your tv screen attracts dust.
638239
A conductor will allow electricity to pass through it, an insulator will not
355445
Newspaper (and most paper) are good insulators.
29235
air-it is all about the air
1088099
insulators ; conduction
831022
Chemically pure water is an electrical insulator.\n\nEven the least impurity, even the least amount of any dissolved ion, will convert it into a conductor.  Even dissolved CO2 will provide the ionic activity to make water conductive