The best ideal black body is
Lamp of charcoal heated to high temperature
Metal coated with a black dye
Glass surface coated with coalter
Hollow enclosure blackened inside and having a small hole
Next Question
The earth intercepts approximately one billionth of the power radiated by the sun. if the surface temperature of the sun were to drop by a factor of 2, the average radiant energy incident on earth per second would reduce by factor of