Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Students' Concepts in Understanding Of Sound   The article describes alternative concepts in understanding of sound observed
among students at the elementary, high school and college level. The research
confirmed some previously found alternative concepts and pointed to several
others. A majority of the difficulties were found to be common to all levels.
Also the percentage of students, who express alternative concepts, is nearly
the same at all educational levels. However the percentage of students who
clearly don't have alternative concepts, in general increases with educational
level.
  One set of observed difficulties, as a whole, compose conceptually structured
and coherent, but naive picture on propagation of sound. Data were collected
through written open-ended test questions on sample of 287 pupils and students
in Split, Croatia 1997.

15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph