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A Little Challenge

  1. Mar 13, 2012 #1
    While I was strolling across a race track the other day under intense sunlight, I found myself pondering over an interesting little problem and I would like to hear opinion about it.

    Cutting to the chase: would I be hit by more reflected sunlight if I walked on the yellow, more reflective track, but at the same time having two blue, less reflective tracks on the sides, as in Fig. 1, or if I walked on the blue track, with two yellow tracks on the side, as in Fig. 2?

    Is it just a matter of calculating the areas in the image? What do you think?

    Attached Files:

  2. jcsd
  3. Mar 13, 2012 #2


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    Staff: Mentor

    Which way is the Sun shining?
  4. Mar 13, 2012 #3
    For the sake of simplicity, let's say it's directly above my head (in the zenith).
  5. Mar 13, 2012 #4


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    Staff: Mentor

    How wide is each coloured track?
  6. Mar 14, 2012 #5
    How do you define getting hit by reflected sunlight?

    This your whole body? Or just your face?
  7. Mar 14, 2012 #6
    Nice questions! The tracks are 1m wide, and I'm thinking just about my face.
  8. Mar 14, 2012 #7
    Then I don't see how it would not simply come down to simply calculating the area of each color in the image. By glance I'd say that you'd get more reflected sunlight on your face if you were running on a blue track, and less if you were running on a yellow track.
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