This is a question from my physics text book. Underneath there is a picture of a guy trying to pull a weight by a chain. He is holding the chain horizontally and with both hands. im confused......thank you for your help!
2006-12-03 06:18:30 · 9 answers · asked by Anonymous in Science & Mathematics ➔ Physics
The chain has weight of its own. The fraction of the applied force which goes into raising the middle part of the chain reduces as the chain becomes nearly straight. That fraction reduces so much as the chain becomes nearly straight that it would require an infinite amount of force to eliminate the last little bit of sag. If you look at the chain in any sagged position, the amount of applied force which is vertical is related to the horizontal and vertical distances between where the chain is gripped and the low point of the sag. The greater either of these distances is compared to the other, the more of the force which will work in the same direction. As the chain becomes nearly straight, the horizontal distance from grip to sag becomes much greater than the vertical distance from grip to sag, so the amount of applied force which goes into further straightening of the chain becomes very, very small.
2006-12-03 06:31:44 · answer #1 · answered by PoppaJ 5 · 1⤊ 0⤋
The problem is that he is pulling on the chain in the x direction and gravity is pulling on the chain in the y direction. The tension in the chain approaches infinity as the chain becomes more straight. In theory the chain could be straighted if an infinite force were applied. However in the real world the chain will not sustain an infinite tension and will snap. This is the same effect you see with suspension bridges where the cables droop and also on power lines.
Anywhere that a non-rigid material is draped across two points the material will always have a sag. The more tension applied to the cable the less the sag but it will always have a little.
2006-12-03 06:50:04 · answer #2 · answered by Anonymous · 1⤊ 0⤋
The chain is not straight because the horizontal force the man exerts on the chain is not the only force acting on it. Gravity also acts on it. And the resultant force on the chain is the combination of the two forces acting on it. The resultant force is the vector formed by the horizontal force that the man exerts, and the vertical force exerted by gravity ... and that resultant force isn't horizontal or vertical, it is at some angle in between two. The exact angle depends on the relative strengths of the two forces. And no matter how strong the man is, he can't exert the only force on the chain, because there will still be a little force exerted by gravity that will keep it from being pulled entirely straight and horizontal.
2006-12-03 06:28:45 · answer #3 · answered by yahoohoo 6 · 1⤊ 0⤋
I'll try a short answer. It's a force vector problem. The man pulls horizontally. Gravity pulls on the middle of the chain downward vertically. The man's force does not have a upward vertical component to offset gravity. Therefore it will never be straight.
2006-12-03 06:52:45 · answer #4 · answered by Alan J 3 · 1⤊ 0⤋
The problem is that he is pulling on the chain in the x direction and gravity is pulling on the chain in the y direction. The tension in the chain approaches infinity as the chain becomes more straight
2006-12-06 15:53:19 · answer #5 · answered by praveenplp 2 · 0⤊ 0⤋
The chain has mass, so gravity will pull it downward. Thus it will necessarily dip at the middle to an extent.
2006-12-03 06:22:55 · answer #6 · answered by Robert A 2 · 0⤊ 1⤋
Tensile strength of the chain
2016-03-13 03:01:26 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Chain is simply to heavy. Try it with string.
2006-12-03 06:32:48 · answer #8 · answered by spir_i_tual 6 · 1⤊ 0⤋
there is not enough information in the question to properly answer it. What is the chain attached to? How? Is there a pulley involved?
2006-12-03 06:22:36 · answer #9 · answered by websnark 2 · 0⤊ 3⤋