Re: Why do I feel the heat from an electric heater that's ABOVE me?

Dear David

good ovbservation, good thoughts !

there are three basic mechanisms of heat transfer
(1) conduction (a hot body is in contact with a colder body ...)
(2) transport by 'convection' i.e. a warm substance, such as hot water 
moves from one place to the other and last but not least
(3) radiation.

No. 3 is the answer to your question. Heat can indeed move from one body 
to another even if there is nothing in between (just think of the sun and 
the earth) ! Heat radiation is something like usual light but with a longer 
wavelength. In a sprectrum, e.g. a rainbow, it follows behind the red color 
and thus is also called infrared (IR) radiation. It is invisible to our 
eyes but can be felt if one feels the warmth of the sun on your skin.

The next question you might ask is HOW light can heat things up. In the 
history of physics this question has long been a mystery. In one modell, 
Light and other forms of electromagnetic radiation "consists" of electric 
and magnetic fields who contain energy. These fields act on electrically 
charged particles and accellerate them (just like a magnet attracts a piece 
of iron). Faster particles mean higher temperatures.