Fall down of an long elastically vertically placed rod

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The discussion centers on the behavior of a long elastic rod falling vertically, with one end fixed on the ground and the other free. Observers note that the free end bends backward, forming an arc, and debate whether this is an optical illusion due to its velocity or a real mechanical bending. A thought experiment is proposed, comparing the rod's behavior when held horizontally to its falling state. Participants express differing views on whether the rod actually curves during its fall. The conversation highlights the complexities of motion and perception in elastic materials.
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Let`s observe fall down of an long elastic vertically placed rod which has two point A and B. Point A is being placed on the ground and not moving, Point B is being free. We observe that the free ending is bending backwards and gets an arc shaped form. In your option, is it an optical illusion created from the velocity of free ending or is there rally a mechanical bending place? If there is a bending, what is the reason of its happening? Not mentioning here resistance of an air. P.S Sorry for my english
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Hello dodi, :welcome:

Google 'chimney breaks' -- it's the same root cause
 
dodi8 said:
Let`s observe fall down of an long elastic vertically placed rod which has two point A and B. Point A is being placed on the ground and not moving, Point B is being free. We observe that the free ending is bending backwards and gets an arc shaped form. In your option, is it an optical illusion created from the velocity of free ending or is there rally a mechanical bending place? If there is a bending, what is the reason of its happening? Not mentioning here resistance of an air. P.S Sorry for my englishView attachment 219187
To answer this, here is a thought experiment: You hold the rod horizontally by applying simple supports at its ends. Does the rod curve anything like what you appear to observe when it is falling?
 
BvU said:
Hello dodi, :welcome:

Google 'chimney breaks' -- it's the same root cause
thank you for any attention
 
Chestermiller said:
To answer this, here is a thought experiment: You hold the rod horizontally by applying simple supports at its ends. Does the rod curve anything like what you appear to observe when it is falling?
thank you for answer. i think the rod does not curve anithing
 
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