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Shadow formation

  1. Apr 19, 2014 #1
    How should I place three objects for e.g three pencils so that no shadow is formed for them throughout the day(light source:sunlight to be considered)??
  2. jcsd
  3. Apr 19, 2014 #2


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    Off the top of my head I'd say make sure they point exactly at the sun. However, since the sun moves over the course of the day I can't see any way to make three stationary pencils create no shadow.
  4. Apr 19, 2014 #3


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    In the shadow of a larger object.
  5. Apr 19, 2014 #4
    But the image of first object will form and it will be visible and i am assuming all objects of equal size.
  6. Apr 19, 2014 #5

    What I was thinking was of an orientation in which light reflected from one object fall over the shadow of second object.Is it possible?
  7. Apr 19, 2014 #6


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    No. You might be able to accomplish something in a controlled lab environment using mirrors and such, but not with just a couple of pencils.
  8. Apr 19, 2014 #7
    Why not? 2nd pencil will reflect light and if i can make the light pass through shadow of 1st pencil the shadow will not form.

    I wish to find the angles at which i should place them so that no shadow is formed irrespective of position of sun.
  9. Apr 19, 2014 #8


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    A pencil is not reflective enough to do this.
  10. Apr 19, 2014 #9
    ok let us consider mirrors now how could it be done.
  11. Apr 19, 2014 #10


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    I don't know. I'm not sure you can, especially since you are keeping the mirrors/pencils stationary while the sun moves.
  12. Apr 19, 2014 #11


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    you will still find that the reflected light is weaker than the direct sunlight on the first pencil
    and it is going to form a shadow but much weaker
    and the second pencil is still going to produce a shadow that isn't going to be "removed"

    I cannot see any way that it could be done short of what AT said
    "Putting the three pencils out of direct sunlight"

  13. Apr 19, 2014 #12

    Vanadium 50

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    Code (Text):

    printf("OP: How do you do this?"\n);
      printf("Others: you can't.\n");
      printf("OP: I think you can.  How?\n");
    Thread closed.
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