>> Your prof was correct. Semantic domains, etymology, and all those >> little tidbits of trivia are interesting- but not useful in the final >> analysis because words gain meaning only from context. >[....] >> To isolate a word and assign it meaning is futile. >[....] > >There is more context to the text than the words proximate to >the text.
When looking at brightness specifications of LEDs, the most common specs available are luminous intensity (usually measured in units of candelas or millicandelas) and viewing angle (measured in degrees). The brightness of 1 candela is roughly around the same brightness as a common candle. A millicandela, or mcd, is 1000 times less bright than a candela, hence the prefix milli-. 1000 millicandelas = 1 candela. Since light is not always evenly dispersed, the viewing angle of a light source is very important.
Brightness temperature is the temperature a black body in thermal equilibrium with its surroundings would have to be to duplicate the observed intensity of a grey body object at a frequency.This concept is extensively used in radio astronomy and planetary science.the Intensity or Brightness) is the amount of energy emitted per unit surface area per unit time per unit solid angle and in the frequency range between and; is the temperature of the black body; is Planck's constant; is frequency; is the speed of light; and is Boltzmann's constant.