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enter image description here

Look at these two photos of my shadow from sunlight.

Case 1: My shadow is separated from the shadow of the ceiling and my head is round.

Case 2: But when I walk a little more and the shadow of my head and the shadow of the ceiling are almost together, the shadow of my head tends to deform. Why?

Edit: Ok. The deformation is because the sun is not a point source and there are fuzzy shadows. But when I look the second picture only my head is deformed and not the ceiling, why?

Here is another picture.

enter image description here

Julian
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1 Answers1

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I have notices this too. If you look carefully, your shadow is not sharp at boundaries. The boundaries has a thin band of light shadow which when you look individually is not easily noticeable. When two shadows come close, the light band of two shadows combine to form darker shadow and it looks like one of the shadows is deforming, or extending.

You see your shadow deforming because rest of the boundary of ceiling has only its own shadow. Where the two meet, only that place the two light bands combine and cause darker shadow giving an impression that your head shadow is deforming.

The thin lighter band is due to bending around the corners, do not recall what the name of phenomenon is, may be diffraction.

When the two shadows come closer, the two objects (you and the ceiling) are actually blocking light path , there is no boundary and diffraction does not take place at that location.

kpv
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