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Shadow formation

by jaeson
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jaeson
#1
Apr19-14, 12:10 AM
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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)??
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Drakkith
#2
Apr19-14, 12:43 AM
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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.
A.T.
#3
Apr19-14, 01:02 AM
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Quote Quote by jaeson View Post
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)??
In the shadow of a larger object.

jaeson
#4
Apr19-14, 01:17 AM
P: 5
Shadow formation

Quote Quote by A.T. View Post
In the shadow of a larger object.
But the image of first object will form and it will be visible and i am assuming all objects of equal size.
jaeson
#5
Apr19-14, 01:17 AM
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Quote Quote by Drakkith View Post
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.

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?
Drakkith
#6
Apr19-14, 01:20 AM
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Quote Quote by jaeson View Post
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?
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.
jaeson
#7
Apr19-14, 01:35 AM
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Quote Quote by Drakkith View Post
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.
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.
Drakkith
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Apr19-14, 01:39 AM
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Quote Quote by jaeson View Post
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.
A pencil is not reflective enough to do this.
jaeson
#9
Apr19-14, 01:43 AM
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Quote Quote by Drakkith View Post
A pencil is not reflective enough to do this.
ok let us consider mirrors now how could it be done.
Drakkith
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Apr19-14, 02:02 AM
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Quote Quote by jaeson View Post
ok let us consider mirrors now how could it be done.
I don't know. I'm not sure you can, especially since you are keeping the mirrors/pencils stationary while the sun moves.
davenn
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Apr19-14, 02:53 AM
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Quote Quote by jaeson View Post
ok let us consider mirrors now how could it be done.
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"

cheers
Dave
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#12
Apr19-14, 06:46 AM
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printf("OP: How do you do this?"\n);
for(;;)
  printf("Others: you can't.\n");
  printf("OP: I think you can.  How?\n");
}
Thread closed.


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