For families & teachers
Why do shadows move?
A shadow forms where an object blocks light. Move the light, and the blocked area can move too—even when the object stays in the same place.
Try the adventure
Imagine light travelling along straight paths from a flashlight. A ball stops some of those paths from reaching the table behind it. That darker area is its shadow. Shine from the left and look for the shadow on the other side. Move the flashlight to the right and the shadow changes direction. A shadow is not a dark object attached to the ball; it is a place receiving less light from that source. Other light in the room may still reach it.
Explore together
- Open the light lab and find the flashlight, the ball and its shadow.
- Move the flashlight slowly across the table using the scene or the paper tab. Watch the shadow rather than the flashlight.
- Pause, predict which way the shadow will move next, then move the light to check your idea.
One thing to remember
Keep one thing changing at a time so the cause is easy to spot. To try a similar idea at home, shine a small flashlight at a toy in front of a wall and move only the flashlight. Ask a child to describe the change before you explain it. Keep the beam away from eyes.
Science reference: NASA ↗
