Bigger Wheels Roll Down Hill Faster: The Reason?

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SUMMARY

The discussion centers on the physics of bicycle wheels and their impact on speed when rolling down a hill. It is established that larger wheels experience fewer revolutions, which reduces friction and can contribute to faster descent. The relationship between translational and rotational energy is highlighted, specifically through the equation E(translation)=1/2mv^2 + E(rotation)=1/2 I w^2, where 'I' represents the moment of inertia and 'w' is the angular velocity. However, the conversation also raises the complexity of these dynamics, suggesting that larger wheels may not always lead to faster speeds due to their moment of inertia.

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daniel_i_l
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I noticed that if two bicycles roll down a hill, then the one with bigger wheels will get to the bottom first (I tested this with my brother). I could only think of one explanation: The bigger wheels make less revolutions and thus have less friction. Is that the reason? Are there other ones?
Thanks.
 
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Differing wheels do make a difference as the energy goes into rotation as well as movement. E(translation)=1/2mv^2 + E(rotation) = 1/2 I w^2. Where w= 'omega' = angular velocity. I is the moment of inertia which depends on the structure of the wheel.
 
But that would mean that a bigger wheel would roll down more slowly.
 

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