Fig. 270. ILLUSTRATION OF THE FALL AND REDEVELOPMENT OF POTENTIAL IN AN
ELECTRIC CIRCUIT.
The fall of potential in a circuit in portions of it is proportional to
the resistance of the portions in question. This is shown in the
diagram. The narrow lines indicate high and the broad lines low
resistance. The fall in different portions is shown as proportional to
the resistance of each portion.
Fig. 271. DIAGRAM OF FALL OF POTENTIAL IN A CONDUCTOR OF UNEVEN
RESISTANCE.
Potential, Magnetic.
The magnetic potential at any point of a magnetic field expresses the
work which would be done by the magnetic forces of the field on a
positive unit of magnetism as it moves from that point to an infinite
distance therefrom. The converse applies to a negative unit.
It is the exact analogue of absolute electric potential.
The potential at any point due to a positive pole m at a distance r is
m/r;. that due to a negative pole - m at a distance r' is equal to
-m/r';. that due to both is equal to m/r - m/r' or m(1/r - 1/r').
Like electric potential and potential in general, magnetic potential
while numerically expressing work or energy is neither, although often
defined as such.