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Black car vs. white car

edited November -1 in The Show
On 5/8/10 show, the caller (from Ft. Lauderdale) asked if a black or white car would heat up more. Theoretically, Click & Clack were correct. Also, the Mythbusters have tested this, and found the following (taken from http://mythbustersresults.com/episode38):





SPINOFF: A black car heats up faster than an identical white car. (From Pilot 2)

CONFIRMED

A fan wrote in and asked a follow up question: "Does the color of a car affect the way it heats up?". The MythBusters used two identical cars, one black the other white and left them both out in the summer heat with thermometers in both. By mid-afternoon the black car had heated up to a temperature of 135 ?F while the white car topped off at 126 ?F, almost 10 degrees cooler.
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Comments

  • Cool.

    (sorry, couldn't resist)
  • edited May 2010
    Most cars and clothes in the Middle East are white, in spite of having to be washed more often than black. In some countries the religion dictates black, but these are very much in the minority.
  • edited May 2010
    More specifically, it may not be so much a question of which is hotter or cooler, but how black or white allows heat equilibrium. Black color better allows the transmission of heat: heat flowing from a location of higher to lower temperature for equilibrium; while white conversely, is more resistive to the flow of heat, thus promoting a difference in temperature. That is why a black potbelly stove seems to radiate heat so well; but if one were to make that stove white, the stove may be hotter inside and the metal of the stove may be hot, while it would not seem to be as hot because less heat is radiating, or, flowing away from the source. If that stove continued to get hotter however, it may be expected that the function of heat being forced out would tend to turn that stove black: resistance breaks down. On a cold night, the same amount of heat would keep the inside of the white car warmer, while when It is hotter outside the white car will resist warming. Black both absorbs and radiates heat well, transmits that is, so whether the interior is black or white is also a factor in heat coming in from the outside. Maybe that is the social intimate feeling derived when people are dressed in black: body heat would be more sensed when two people in close proximity are wearing black.
  • edited May 2010
    I once owned a 1987 Mazda RX7 and quickly ditched it for the sole reason that it was black. Not only was it noticably hotter, but the finish was much harder to maintain. Dust, hard water stains, pollen, fuzz, hair, belly button lint all show up more on a black car. Also, scratches and swirl marks are much more pronounced in a black finish than most other colors. Sure, it looks uber cool, but from a practicality standpoint, it's requires the most care.
  • edited May 2010
    True that. I noticed that in Iraq, Qatar and Kuwait there were a lot of black cars. More in Qatar and Kuwait. I asked our interpreter why, in some of the hottest parts of the world, someone would even consider a black car. His answer was that it's a status symbol. If you have a white car, then you're practical, thus poor ('Poor' meaning that you only have ONE kajillion bazilion dollars in the bank). If you have a black car, then you have a cool garage, a servant to polish it and to cool it off before you get in. Keep pumping that gas, world. You're paying for modern day footmen.
  • edited May 2010
    Absolutely the dark car would heat up quicker. I was stationed in Hawaii many years ago and had a white International Scout. After living on the North Shore for a couple of years, the car developed a lot of rust spots. I had it sanded down and repainted a dark green. Boy what a mistake that was! On hot day, which were many, the poor air conditioner could not keep up like it could when the Scout was white. Therefore I had the advantage of scientifically proving the point. Because all other factors remaind equal except the color. Plus I had the advantage of experiencing two years of seasonal change in a white vehicle and almost two in a dark green one.
    Sure loved that Scout. It was a sad day when International quit making them. They were prone to rust though.
  • edited May 2010
    Buy one of those window shades you put in the front windshield and call it a day
  • Black cars heat up more. Black interiors compound the problem.

    The color we see is the combination of the frequencies in the visual spectrum that are reflected rather than absorbed. Black means all of the energy in the visual spectum is absorbed. White means that it's all reflected.

    Realize that all "color" is is a combination of those frequencies in the electromagnetic spectrum that excite the cells in the retinas in our eyes. That range of frequencies is called the "visual spectrum". If no frequencies in the visual spectrum are reflected back at our retinas, none of the cells are excited and we see "black". If all the colors are reflected back at us, all out retinal cells are excited and we see "white".

    The more radiant energy (light is electomagnetic energy) is absorbed, the more the item heats up.

    Black = electromagnetic energy in the visual spectrum all absorbed = heat
    White = electromagnetic energy in te visual spectrum all reflected = less heat (other frequencies outside the visual spectrum are absorned, so heat will happen).

    Some frequencies of electromagnetic anergy pass right through, such as radio waves.
  • edited May 2010
    There is a reason for the white roofs on school buses after all! I also recall in the older NASA missions half the rocket was white and half black, to either absorb or reflect heat, whichever was needed. C):-)
  • edited May 2010
    @Harough:

    Almost everything in your post reading "More specifically.... wearing black" is wrong.
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