On a sunny day, have you ever noticed that sometimes your shadow is long and sometimes it is short? Try this experiment to find out why.
What to Do
Stand a plastic bottle on a piece of paper on a sunny sidewalk or driveway. Trace the bottle’s shadow onto the paper. Every hour or two, put the paper and bottle in the same position and trace the shadow again. Notice how the position of the shadow changes.
How It Works
The bottle blocks the light that comes from the Sun, creating a shadow on the paper. The shadow moves throughout the day as the Sun appears to move across the sky, from the east in the morning to the west toward the night. The Sun really stays in the same place, but its position in our sky changes as the Earth spins. At the beginning and end of the day, the bottle’s shadow is long because the Sun is shining on the bottle from the side. In the middle of the day, the shadow is shorter because the Sun is shining on the bottle from above.
The shadow will also reach in the opposite direction of where the sunlight is coming from. You can guess where the Sun is in the sky from the size and direction of your own shadow!
Now listen to a poem about shadows big and small.