- #1

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Ok, so the trick is shown in the following link...

could anyone explain how this is accomplished?

could anyone explain how this is accomplished?

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- Thread starter rvgene
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- #1

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Ok, so the trick is shown in the following link...

could anyone explain how this is accomplished?

could anyone explain how this is accomplished?

Last edited by a moderator:

- #2

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Just get 4 friends and try it??

- #3

DavidSnider

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- #4

Ryan_m_b

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for example, the pivot is at the head, and there is a anticlockwise moment due to the centre of gravity and a clockwise moment due to the normal force at the feet?

- #6

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Consider each person individually as an object resting on two supports. The weight of each person is supported by 1.) their own legs from the knees down, and 2.) the legs, from the knees down, of the person on whose knees their back is resting. The center of gravity of each person is somewhere between their knees and the point where their back touches the next persons knees, though it is much closer to the latter. I just experimented with getting myself into this position with my back resting on the seat of a chair. If you try that you'll see there's much more pressure on your back than on your feet. In the group situation each person's knees are supporting a little bit of their own weight and most of another person's weight. If you could determine the center of gravity of each person in this position you could work out how much of their weight is supported by their own knees and how much by the knees of the next person.

for example, the pivot is at the head, and there is a anticlockwise moment due to the centre of gravity and a clockwise moment due to the normal force at the feet?

- #7

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Okay, that was amusing.

- #8

richytherude

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