A shadow is a dark area where light from a light source is blocked by an opaque object [not able to be seen through; not transparent].
So let's take a light source, like the Sun.
.....and let's take an opaque object, like a boy.
Remember we live in the Northern Hemisphere and therefore the Sun always appears from the South. The Sun also always rises in the East and travels in an arc to set in the West.
There is a difference in the height the Sun manages to achieve in the arc throughout the seasons. It manages the greatest height in Summer and the lowest height in Winter.
So on this particular day at 6 am the Sun rises and is low in the morning sky. You see that the shadow is much longer than the boy's body.
By 9 am the Sun is beginning its climb in the morning sky. The shadow is now almost the same length as the boy's body.
At 12 noon the Sun is at its highest point on the arc. The shadow is very small and close to the boy's body.
By 3pm the Sun is getting lower in the afternoon sky. The shadow is longer than it was at noon.
Finally, at 6pm the Sun is setting in the evening sky. The shadow is long. Notice that it is on the other side to where it was at 6am.
What you should now know?.....
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