When you run with the firki in your hand or blow air on it, the firki rotates. This rotation is caused by the wind.
Class 6 Science NCERT Chapter 11
Chapter 11 Nature’s Treasures
How does a firki (paper pinwheel) demonstrate the effect of wind?
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A firki (paper pinwheel) demonstrates the effect of wind by spinning when air flows against its blades. The wind’s force transfers energy to the blades, causing them to rotate, showing wind’s ability to move objects.
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