Rensselaer Republican, Volume 27, Number 18, Rensselaer, Jasper County, 27 December 1894 — Dynamo, Volt, Ohm and Ampere. [ARTICLE]

Dynamo, Volt, Ohm and Ampere.

The aliove odd looking string of words, is not a volley of new-fash-ioned ‘‘cuss-words,” nor yet is it a sentence in Valupuk or Sanscrit, but only a few words in general use wherever electricity is used to any extent, especially lor lighting pur poses. The meaning of the words is thus t xplained by D. morest’a Magazine:

A dynamo is a large machine made with two electro-magnets which have massive iron cores on which are wound large coils of cotton-covered copper wire. One of these, called the Held msgnet, is usually shaped like a common steel horse shoe magnet, and has two large hole pieces, which partly inclose a circular space in which the other magnet, called the armature, and shaped like a ring or cylinder, revolves. A steam engine or Water whtel is required to revolve this armature in opposition to the magnetic attraction, which tends to ke< p it from revolving, and is very slight at first, but increases with the rotation, so that, in a second or two, a powerful force is required to turn the armature; and this rotation generates electricity in the wire coils; which are connected with the wires by which it is conveyed to the houses. Vu.t, ohm and ampere are merely convenient terms used to represent th° ”nits by which the pressure, resistance and volume of the current are measured. The volt is the unit of pressure by which the current is forced through the wires, as steam, gas < r water is forced through pipes. The obm is used to mt asure the elec- ' • -isislance oi the wire, wh'ch op- ' •'S friction in pipes the flow of steam, unpere is used to of current which gh a wire by a 'n opposition to

a resistance of one ohm, the volume of Uie-eurrent. m amperes,. being as., certained by dividing the pressure, in volts, by the resistance, in ohms. A current having a pressure of one hundred volts, and a resistance of one hundred ohms, would have a volume of one ampere; while a current having a pressure of one-hundred volts, and a resistance of ten ohms, would have a volume of ten amperes, and so on.