Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Energy Conversion in Lifting Mass Vertically using a DC Electric Motor
  by Observing Required Time to Lift Object for a Certain Height   In lifting mass vertically using a DC electric motor energy conversion from
electric energy, through intermediate kinetic energy, to gravitation potential
energy shows that time required {\Delta}t to lift load mass m for height h is
dependent quadratically to m. Several approaches to explain the experiment
observation are discussed in this work, from ideal energy conversion to
numerical solution from differential equation.

5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess