Treatise on Electricity and Magnetism Fig 04

Lines of Forces and Equipotential Surfaces.

Figure IV represents the equipotential surfaces and lines of force due to three electrified points A, B and C, the charge of A being 15 units of positive electricity, that of B 12 units of negative electricity, and that of C 20 units of positive electricity. These points are placed in one straight line, so that

A

B

=

9

{\displaystyle AB=9}

,

B

C

=

16

{\displaystyle BC=16}

,

A

C

=

25

{\displaystyle AC=25}

.

In this case, the surface for which the potential is unity consists of two spheres whose centres are A and C and their radii 15 and 20.

19th century diagrams a treatise on electricity and magnetism diagrams design

1973

A treatise on electricity and magnetism. Oxford : Clarendon Press. Original was here

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