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@pratap singh, upendra • 16 Jun, 2013
I recently learnt that the best color to make an umbrella for use inn summers is to have white surface on the top and the bottom surface painted black.
What could be the scientific reason for it? Of course it concerns itself with the degree of absorption and emission but the exact reason is something I am struggling for.
Please guide me.
regards,
proffy
What could be the scientific reason for it? Of course it concerns itself with the degree of absorption and emission but the exact reason is something I am struggling for.
Please guide me.
regards,
proffy
@Kaustubh Katdare • 16 Jun, 2013
Do you really think that this thread should be posted in Electronics / Electrical & Communications section? Moving it to chit chat.proffyI recently learnt that the best color to make an umbrella for use inn summers is to have white surface on the top and the bottom surface painted black.
What could be the scientific reason for it? Of course it concerns itself with the degree of absorption and emission but the exact reason is something I am struggling for.
Please guide me.
regards,
proffy
@lal • 16 Jun, 2013
White colour reflects most incident rays including IR falling on it. If it was black on the top, it would absorb radiations incident on it and get hotter. That will make the person under a black umbrella sweat more!
@Abhishek Rawal • 16 Jun, 2013
This is elementary science.
Black color absorbs more heat & white color reflects more IR Radiations so absorbs less amount of heat than other colors.
Black color absorbs more heat & white color reflects more IR Radiations so absorbs less amount of heat than other colors.
@Ramani Aswath • 16 Jun, 2013
Actually the thermal mass of the very thin fabric used makes this somewhat irrelevant. In Kerala one does get brollies with white fabric on top with black below. From emissivity point of view the best is an aluminized film.
@Ramani Aswath • 24 Jun, 2013
This may be of use:
https://engineering.stanford.edu/news/new-type-solar-structure-cools-buildings-full-sunlight
https://engineering.stanford.edu/news/new-type-solar-structure-cools-buildings-full-sunlight
6.4k views
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