What A Dangerously Low Bmi

After the first snow has fallen and now the sun is shining, it is very bright in the open. The light is reflected, the energy of sunlight is reflected back and the snow is melting slowly. The white clouds glow in the clear air.
The full-literal use of reflection in this sense, reflection, as in light reflection. So no light reflection, as one might think would perhaps, at least not according to the official use of language, see -reflection or reflection-lead of the latin-word-. Although I was considered appropriate for the physical use of reflection, to it by the medical reflex response of the body to distinguish a certain charm clear. In English there is this difference as a "reflection" and "reflex". In the German physics textbooks used correctly but formal reflection, I have to and not necessarily stick to it.

The stronger the reflection, the brighter the objects we see (if light is available). The body does not reflect light is black, we do not see them. We see them only because they are different from the bright environment. If we attach several small black objects against a black background, we can not see them - if they really perfect black. But this can hardly be fulfilled really, at least at corners and edges, but they mostly reflect a little. Depending on the wavelength of light we perceive the different colors - but that's clearly his own, and not so scarce chapter.

The reflection of light plays for the heat balance of a body a major role. A bright object reflects light and absorbs little energy from the radiation, a dark body correspondingly more. Yes - light is a radiation - electromagnetic radiation. The word radiation is unfortunately occupied so negative, you think almost immediately of the dangers of radiation. Radioactivity is radiation free and X-rays are far from healthy (except in that way, an even greater risk, that can detect and avert a serious illness). Radiation is always harmful - of course not. Without the heat radiation and light of the sun we could not live at all. We need the light to make certain vitamins in the skin can be. Without the heat radiation we would freeze to death.

Back to the heat content of the radiation. If we take the summer in the sun a dark clothing, we will be heated more than a bright clothing. The heat balance of the Earth also depends on how much of the sunlight is reflected and how much is allowed through. However, the warming of the Earth also depends as much on how much of the heat on the earth, can be radiated. As uses of the greenhouse effect. If the composition of the atmosphere changes by CO2 and the like, less radiated and the temperature rises. Also a story in itself, which indeed is well enough known, and almost constantly moves through the media.

If the surface is rough, so the incident light is reflected in all directions when the surface is smooth, preferably there is a mirror reflection. This is on wet roads at night a big disadvantage. The diffuse scattering of one's own lights and the surrounding lights will remain and the road is dark, except the right reflecting lights of oncoming vehicles.

signed me up to the light snow to some unexpected ideas out.