Harper's How to Understand Electrical Work; A Simple Explantion of Electric Light, Heat, Power, and Traction in Daily Life

Harper's How to Understand Electrical Work; A Simple Explantion of Electric Light, Heat, Power, and Traction in Daily Life

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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 edition. Excerpt: ...wires, and thus making the body or a part of it form a portion of the circuit, "direct application" is obtained. Insulation is brought about the same as in the case of the static machine. Induction-coils In addition to the high-frequency coil mentioned above there are two other classes of induction-coils--one in which the secondary coil is moved over the primary coil and by means of which short sparks are obtained and a wide range of current adjustment; and the other, the common medical induction-coil. The latter is often enclosed in a case with batteries, electrodes, etc., and constitutes a convenient portable instrument. The ordinary induction-coil is made up as follows: Insulated from and wound around a core of soft iron wires is the primary coil comprising a few layers of copper wires. Outside of this is wound the secondary coil consisting of very many turns of fine, insulated copper wire. Great care is taken with the insulation of the secondary coil because of the high voltage generated in it, and oftentimes it is wound on ebonite or hard rubber bobbins and even divided into sections. The primary circuit is interrupted by a vibrator in order that the change of flux might generate in the secondary wires an electromotive force. The terminals of the secondary are connected to the movable rods by means of which the length of the spark-gap may be varied. Fig. 8 shows diagrammatically how the various parts are connected, the upper lines showing how high-frequency currents are produced. Roentgen Rays Since December, 1895, when Professor Roentgen announced the nature of his striking discovery, Roentgen rays or, as they are more popularly known, X (meaning unknown) rays, have been employed for many purposes in the hospitals. The surgeon...show more

Product details

  • Paperback | 92 pages
  • 189 x 246 x 5mm | 181g
  • Rarebooksclub.com
  • Miami Fl, United States
  • English
  • black & white illustrations
  • 1236649311
  • 9781236649317