Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Toy models for the falling chimney   In this paper we review the theory of the ``falling chimney'', which deals
with the breaking in mid-air of tall structures, when they fall to the ground.
We show that these ruptures can be caused by either shear forces, typically
developing near the base, or by the bending of the structure, which is caused
primarily by the internal bending moment.
  In the latter case the breaking is more likely to occur between one third and
one half of the height of the chimney. Small scale toy models are used to
reproduce the dynamics of the falling chimney. By examining photos taken during
the fall of these models we test the adequacy of the outlined theory. This type
of experiment, easy to perform and conceptually challenging, can become part of
a rotational mechanics lab for undergraduate students.

14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
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The categories of this paper are: nlin
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th