Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A novel method for measurement of the refractive indices of transparent
  solid media using laser interferometry   A novel method is proposed to measure the refractive indices (RIs) of the
materials of different transparent solid state media. To exploit the advantage
of non-contact measurement laser beam interferometry is used as an effective
technique for this purpose. The RIs of materials are also experimentally
determined with the aid of another laser based simple method. The derivations
of the working formulae for both the methods are presented. The experimental
values of RI of any glass sample found by the different methods are consistent
with each other and fall within the range of known values of RI for glass. Both
types of experiments can be set up rather easily in an undergraduate
laboratory. They can supplement other methods of finding refractive index like,
for example, methods based on the use of a spectrometer.

15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
1
The categories of this paper are: cs