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In a tug-of-war match today, my summer camp students were very concerned about putting the biggest people at the back of the rope. Is there any advantage to this strategy?

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When the rope breaks, the big people are on the bottom of the pile! –  JoeHobbit Jun 30 '11 at 8:18
    
The wikipedia page on it shows some professional rope pulling, it seems the "biggest" (what ever that means exactly in English) are placed always at the ends. My guess is "psychology", if the smaller ones were behind, they lack sight of what is going on, and they feel obsolete. The very last one at each end can sling the rope around his back/shoulders, this is reason to place the biggest/strongest last. –  Georg Jun 30 '11 at 10:16

4 Answers 4

up vote 1 down vote accepted

Think of how much horizontal force you can apply. The puller, is leaning horizontally, and pushing (at an angle on the ground), and vertcal forces and rotational torque must separately balance. The more the puller can lean backwards, and the lower the rope, the more horizontal force he can apply. Presumably he can lean more, and get the rope lower from the back of the line.

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The link given in the question says: ""Lowering ones elbow below the knee during a 'pull' known as 'Locking' is a foul, as well as touching the ground for extended periods of time. "" –  Georg Jun 30 '11 at 17:09

I can see two advantages:

1) the more heavy set the stronger the muscles, so it means a lot of the force is coming on a long arm. The tug is supposed to be linear but rotations will happen, and there will be amplification of the effect as a lever arm. If the rope were solid this is obvious.

2) Think of two people of equal weight,on a see-saw. The one with the shorter distance from the fulcrum is at a disadvantage and has to put in more force to swing. A tug of war has a "fulcrum" at the center where the two teams meet. Putting the heavy players at the end will shift the centre of mass towards the end and will give an advantage in the impulse transfer by a longer distance from the center.

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""If there are two people of equal weight, but share the rope unequally, "" This is a kind of riddle to me. Re "impulse", practice and rules of rope-pulling exclude any "impulse". –  Georg Jun 30 '11 at 10:11
    
@eorg have a look at the definition of "impulse" en.wikipedia.org/wiki/Impulse_%28physics%29 . Where there is force that changes in time there is impulse, which is effectively delta(p) which is what decides who will pull the others over. I will edit the example about "sharing the rope" –  anna v Jun 30 '11 at 10:44
    
@Anna Do you mean a "see-saw"? A swing is usually for one person swinging back a forth. A see-saw is a straight board with a fulcrum in the middle and one person on either end. –  Mark Eichenlaub Jul 2 '11 at 6:32
    
@Mark Eichenlaub sorry, yes a see-saw. You realize english is not my first language, but this I should have known. –  anna v Jul 2 '11 at 18:47

In the pure physics sense, if 3 people that pull 40Lb 30Lb and 20lb the total pull will be 90lb no matter where you put them. Now in the strategy is the last person in line is called the anchor he/she is usually the biggest and strongest of the bunch the next 3 are the pullers they do a straight yank as hard as they can and they are the pre-anchor the rest are heavers. The heavers pull in a rhythm or cycle called by the 1st person in line or the captain and they are arranged by height. The basic strategy depends on the 3 types of human force. The marathon runner “Constant force applied over time.” The sprinter “Grate force over a short time.” And the weight lifter “Exert and hold great power.”

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Yes, if you put the strongest people in the back the rope will be straighter, making it more likely everyone is pulling in the same direction.

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