why the shadow of humane legs on the earth is so clear but the shadow of the head is not?

Question

warriorz13 · Answer

that is the one question i cannot answer my friend

kmazraee · Answer

@Warriorz13 so you haven't any idea about the answer?

warriorz13 · Answer

sorry but no

anonymous · Answer

When an object is illuminated by an extended (wide) light source as the Sun  there are regions of the shadow around the edge which do not totally exclude the light.  In this region you can see part of the Sun.   This region is called the penumbra.  There is also a region where the light of the sun is totally blocked.  This is call the umbra.   The farther behind the object you go you will be able to see more of the Sun.  This results in a wider penumbra and narrower umbra.   In genera areas in the shadow that are closer to the object have wider umbras and narrower penumbra.  See the diagram below

Thus your head being farther from the surface onto which the shadow is cast will have a wider penumbra than you legs which are closer ground.   If you observe your shadow on a  surface that is perpendicular to the Suns rays so that every part of you is at the same distance from that surface you will see no difference in the blurriness  of your head and legs. ( gr|dw:1413390417463:dw|ound)