What makes a shadow?
In the sunshine, your shadow travels with you everywhere you go.
Sometimes it bends in funny places. Sometimes it takes a strange
shape. But it’s always there. On a cloudy day, or in a dark room, you
have no shadow at all. What is your shadow? Where does your shadow go?We have shadows because light moves in a certain way. It travels
outward from its source. It moves in waves, something like ripples in
water. As long as nothing is in the way, the light waves move in one
direction.
But when some of the light waves hit something—you, or a tree, or a
house—they are stopped. Then, on the other side of the thing that
stopped the light waves, there is a dark space—a shadow.Things in a dark room have no shadows because there are no light waves
traveling through the room. And on cloudy days, things have no shadows
because the clouds break up the light waves from the sun. The clouds
soak up some of the waves and scatter the rest of them in all
directions. When the light waves scatter and bounce instead of moving
in one direction, no shadows are formed.
