I'm confused on a scenario. If we roll a ball on a horizontal surface and it rolls without slipping it should eventually stop due to friction. However rolling without slipping means the velocity at the point of contact is always 0. Since kinetic friction always opposes movement and the point of contact has v=0 there's no kinetic friction and static friction only arises when there is some force. Thus there is no friction? Can anyone clarify what is happening, and point to where I'm confused.
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As you are aware, both kinetic friction and static friction are zero when an object rolls with constant velocity. If these were the only forces available the ball will never stop rolling on a perfectly flat surface.
However, there are other sources of "friction". There is air resistance, and also rolling resistance. Rolling resistance is related to the fact that the ball and the plane are not perfectly rigid, they deform a little so that the ball is always climbing over a small hump, causing a small resultant force which opposes motion.
sammy gerbil
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In reality there is no single point of contact but a small but finite area of contact and the velocity of all those points of contact is not equal to zero. So in realtiy there is no such thing as rolling without slipping. But I guess you are right that theoretically a ball with an area of contact --> 0 would not experience any loss of energy.
Daniel
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