Shadows change shape and size depending on where the light comes from. Drag the sun higher or lower and watch the shadow change.
Try it: slide close to 90° for the shortest shadow, like at midday.
Light is a form of energy that lets us see things. It comes from a source — either natural, like the sun or fire, or artificial, like a bulb or a torch. Light always travels in a straight line.
Lets almost all light pass through — you can see clearly through it.
Lets some light pass through, but you can't see a clear image.
Blocks light completely — nothing passes through.
A shadow forms when an opaque object blocks light travelling from its source, creating a dark area on the surface behind it.
Transparent objects like clear glass let light pass through, so they cast little to no shadow. Translucent objects cast a faint, blurry shadow.
A shadow's size depends on the position of the light source. When the light is low (like the sun early morning or evening), shadows are long. When the light is high overhead (like the sun at noon), shadows are short. Moving the object closer to the light source also makes its shadow bigger.
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