30
KINETIC ENERGY OF ELECTRICITY IN MOTION [I]
observed for smaller strengths may easily and in various ways
be reduced to thermal, magnetic, or diamagnetic causes, whose
effect does not increase in proportion to the current, but quickly
reaches a maximum.
RECAPITULATION OF RESULTS AND INFERENCES.
We shall shortly recapitulate the results in order to deduce
from the experiments an upper limit to the quantity μ, the
meaning of which was explained in the introduction.
We start from the formulæ
m =
P(JP-1).
qm
με
21
The quantities occurring here in the various experiments
had the following values :-
1. In the experiments with spirals we had
7 = 130,032,
q= 0.6793,
P=178,500,
P' = 37,840,000,
J = 1.1467,
J' 238.67.
=
The probable error of the various values cannot be stated
exactly, as the corresponding measurements and the sources of
error present were so various. Nevertheless it is certain that
in none of the measurements was an error committed greater
than 1/20 of the whole; and the errors of the calculation,
by which P was determined, cannot, according to what was
said above, reach this amount. Hence, if we assume that the
quantity JP'/J'P, which is compounded from the results, is in
error by 1/20 of its value, in such a way as to hide any
effect of mass perhaps present, we shall obtain a limit which
is most unlikely to be exceeded, namely,
m<178,500
JP'
J'P
·
금
​-
·1),
m<13,356, μ<0·0348 mm².
2. We obtain a smaller limit from the first series of
experiments with rectilinear wires. Here we had
P'
¹ [The fraction is in the original replaced by since P' denotes a mutual
P
P'
2P
inductance, and P there stands for a "potential on itself," which Hertz defines as
half a self-inductance.-TR.]