Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The law of momentum conservation in free microwave cavities containing
  coherent radiation   Using classical electrodynamics, this work analyzes the dynamics of a closed
microwave cavity as a function of its center of energy. Starting from the
principle of momentum conservation, expressions for the maximum electromagnetic
momentum stored in a free microwave cavity are obtained. Next, it is shown
that, for coherent fields and special shape conditions, this momentum component
may not completely average out to zero when the fields change in the transient
regime. Non-zero conditions are illustrated for the asymmetric conical frustum
whose exact modes can not be calculated analytically. One concludes that the
electromagnetic momentum can be imparted to the mechanical body so as to
displace it in relation to the original center of energy. However, the average
time range of the effect is much shorter than any time regime of the
experimental tests performed to measure presently, suggesting it has not been
observed yet in copper-made resonators.

15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc