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Light and shadows

  1. Feb 5, 2012 #1
    I was reading the other day with the light on behind me. I cast a shadow over the book I was reading and was still able to read it (not that surprising). I'd never thought about this before though. Why is it you can read in a shadow but not the dark? I could understand if there was another light source but this was the only one.
     
  2. jcsd
  3. Feb 5, 2012 #2

    davenn

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    hi
    welcome to the forums :)

    well probably cuz there is still plenty of ambient diffuse light, bouncing off the room walls refracting around your body etc etc

    Dark is the absence of light .. cant read like that ;)

    cheers
    Dave
     
  4. Feb 5, 2012 #3
    So the larger the room the harder it would be to read?
     
  5. Feb 5, 2012 #4

    davenn

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    yes
    tho that would also depend on the colour of the walls etc dark paint/light paint etc

    I was going to add to my first post but didnt... now will here....

    try this experiment....

    stand in a room with some one behind you with a decent bright torch (flashlight)
    now go outside on a very dark nite, where there is no ambient streetlight, moonlight etc
    now get you mate to shine the light from behind you again.
    I bet its much harder to see the book let alone the text on the pages :)

    I couldnt do that from my home, I live in a big city it never gets that dark

    Dave
     
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