Friction Conundrum: Why Does Wheel Keep Rolling?

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In the discussion about a rolling wheel, participants explore the direction of friction when no external torque is applied. It is established that friction opposes the relative motion at the contact point, which leads to confusion regarding its direction in relation to angular velocity. The wheel rolls to the right, causing the contact point to move left, suggesting friction acts to the right. However, the relationship between angular acceleration and friction creates a paradox, as angular acceleration seems to oppose the direction of friction. Ultimately, the conversation highlights the complexities of understanding friction in rolling motion, resolving that the initial confusion stemmed from overthinking the problem.
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You have a wheel that is rolling without slipping on the ground, it is being subjected to no outside tourque or pulling force... which way is friction acting and why.
I thought that this would be easy but it turns out to be tricky, if the wheel isn't slipping the velocity equals omega times the radius, and you solve and get a direction of the friction... using work kenetic energy theorem... but that direction always seems to be in the opposite direction itd have to be according to the angular velocity, can anyone help?
 
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Friction always (I'm not 100% sure on this though) opposes motion. If a wheel is rolling right, the part of the wheel making contact with the ground is moving left so the friction vector is pointing to the right.
 
Ok yeah but then the angular acceleration is to the left because the wheel is slowing down... which means that friction should be is the opposite direction right? but angular velcocity should agree with the direction of friction... which means you have two frictions opposing each other
 
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Why are you saying that the angular velocity should agree with the direction of friction? The direction of the angular velocity vector for a wheel is parallel to the axis of rotation. Right?
 
yeah i don't know... you are correct, i think it was one of those things where i was making it harder in my head than it has to be, thanks for your help :)
 

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