- #1
Phrak
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Newton’s Third Law. “To every action there is always opposed an equal reaction: or, the mutual actions of two bodies upon each other are always directed to contrary parts.
“Whatever draws or presses another is as much drawn or pressed by that other. If you press a stone with your finger, the finger is also pressed by the stone. If a horse draws a stone tied to a rope, the horse (if I may say so) will be equally drawn back towards the stone; for the distended rope, by the same endeavor to relax to relax or unbend itself, will draw the horse as much towards the stone as it does the stone towards the horse, and will obstruct the progress of the one as much as it advances that of the other.…” -Isaac Newton
Comment by George Gamow: “Why then, one can ask, is the horse pulling the stone, and not the stone pulling the horse? The answer is, of course, that the difference lies in the friction against the ground. The four horseshoes cling more strongly to the ground than does the stone, and if it were not so, the stone would remain in place and the horse’s hoofs would slide [which doesn’t really answer the question, “why does the stone not pull the horse?”].”
Newton’s law expresses the conservation of momentum between two interacting systems. The momentum lost by one is obtained by the other. An element of momentum, through interaction, is relocated without loss.
Why odes the stone not pull the horse? With all due respect, I don't think that Newton correctly says what he intends to say, nor that George Gamow answers it. Some fresh minds that can look at this without predisposition would be greatly appreciated!
“Whatever draws or presses another is as much drawn or pressed by that other. If you press a stone with your finger, the finger is also pressed by the stone. If a horse draws a stone tied to a rope, the horse (if I may say so) will be equally drawn back towards the stone; for the distended rope, by the same endeavor to relax to relax or unbend itself, will draw the horse as much towards the stone as it does the stone towards the horse, and will obstruct the progress of the one as much as it advances that of the other.…” -Isaac Newton
Comment by George Gamow: “Why then, one can ask, is the horse pulling the stone, and not the stone pulling the horse? The answer is, of course, that the difference lies in the friction against the ground. The four horseshoes cling more strongly to the ground than does the stone, and if it were not so, the stone would remain in place and the horse’s hoofs would slide [which doesn’t really answer the question, “why does the stone not pull the horse?”].”
Newton’s law expresses the conservation of momentum between two interacting systems. The momentum lost by one is obtained by the other. An element of momentum, through interaction, is relocated without loss.
Why odes the stone not pull the horse? With all due respect, I don't think that Newton correctly says what he intends to say, nor that George Gamow answers it. Some fresh minds that can look at this without predisposition would be greatly appreciated!