It is a direct experience, although some intuitive explanation, the sun heats less the further from the zenith, either during the day or through the seasons. Among the various causes, the most prevalent is the height of the Sun above the horizon or equivalently, the value of the angle between the distance to this star segment and the ray pointing to the zenith. This variation produces that the same amount of radiation of energy emitted covers on different amount of surface.
Two ways of looking at the phenomenon:
It is a known fact that suits wear light colors when it’s hot and we are exposed to sunlight. The reason is that light colors reflect more radiation they receive, than dark colors, which absorb more radiation than the first. By absorbing more radiation heat up faster, reach a higher temperature, and transfer more heat to the environment. This experience is intended to show what the relationship between the clear, as to the absorption of radiation, mainly dark colors and heat.
To realize we will expose two cans, one painted white and painted black, in the light of an incandescent bulb of 60 watts, which delivers enough heat to the environment (also can be made in the light of the sun) recording changes temperature until it is almost stable and then graph the results.