KINETIC ENERGY OF ELECTRICITY IN MOTION [1]
3
The amount of this increase depends on the quantities m,
whose meaning we will now consider more closely, basing our
investigation on Weber's view of electric currents. The
presence of the terms involving m is, however, independent of
the correctness of this view and of the existence of electric
fluids at all; every explanation of the current as a state of
motion of inert matter must equally introduce these terms,
and only the interpretation of the quantities m will be
different.
Suppose unit volume of the conductor to contain λ units
of positive electricity, and let the mass of each unit be p
milligrammes. Let the length of the conductor be l, and its
cross-section, supposed uniform, q. Then unit length of the
conductor contains qλ electrostatic units, and the total positive
electricity in motion in the conductor has the mass pqal mgm.
If the current (in electromagnetic measure) be i, the number
of electrostatic units which cross any section in unit time is
equal to 155,370 x 10%, and is also equal to the velocity v
multiplied by qλ.
Thus
v =
155,370 x 106.
φλ
-i,
and the kinetic energy of the positive electricity contained
in the conductor is
=
Εραλ
li2
q
ρ
155,370 x 106) 22
λ
q²
155,3702 x 1012 li2
λ
=
·
The
The quantity /q can be expressed in finite measure.
quantity p.155,3702 x 10/12x, which has been denoted by μ,
is a constant depending only on the material of the conductor;
for different conductors it is inversely as the density of the
electricity in them. Its dimensions are those of a surface; in
milligramme-millimetres it gives the kinetic energy of the two
problem "to make experiments on the magnitude of extra-currents which
shall at least lead to a determination of an upper limit to the mass moved."
It was pointed out that for such experiments extra-currents flowing in opposite
directions through the wires of a double spiral would be especially suitable.
The present thesis is essentially the same as that which gained the prize.