Shadows change for kids because the sun's position in the sky changes throughout the day.
Here's a more detailed explanation:
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The Sun's Apparent Movement: The reference video mentions that the sun appears to be moving in the sky. While the sun isn't physically moving around the Earth, the Earth is rotating. This rotation causes the apparent movement of the sun across the sky from east to west.
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How Shadows are Formed: Shadows are created when an object blocks light. The shape of the shadow depends on the angle of the light source (in this case, the sun) relative to the object.
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Changing Sun Position = Changing Shadows: As the Earth rotates and the sun's apparent position changes, the angle at which sunlight hits objects also changes. This shift in angle results in shadows that are:
- Longer in the morning and evening: When the sun is low on the horizon (morning or evening), the light hits objects at a shallow angle, creating long shadows.
- Shorter at midday: When the sun is higher in the sky (midday), the light hits objects more directly from above, creating shorter shadows.
- In different locations: As the sun moves across the sky, the direction of the shadow also changes, meaning the shadow moves (and may even disappear at certain angles).
In short, the movement of shadows that kids observe is caused by the Earth's rotation and the constantly shifting position of the sun in the sky, changing the angle at which sunlight hits objects.
