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Icicle Frenzy by Trevor Jackson Light

Honorable - Natural Category

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School: Glenbard West

Teacher: Nicholas Szarzak

In this photo, water that collected on the tire of a moving car began to freeze and form icicles and when this process was over, icicles pointed outwards in a circle. Because of the rapidly spinning tire, the centripetal force that is produced has the most important role in the development of the icicles. Centripetal force is center seeking and is the friction between the hubcap of the spinning tire and the water. So this by itself is not the reason the icicles point outwards, rather, it is the water droplets inertia that makes the water move outward. The water droplets want to travel in a linear path, but the effects of the centripetal force pull it continually inward also causing the direction of the velocity to continuously change as the water moves around the circle. Inertia would make the water droplets fly tangentially away from the spinning tire, but the friction from the centripetal force pulls it constantly inward. With the inward force keeping the water close together, the water has time to freeze while inertia slowly pulls it outward, creating icicles around the entire circle.

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