Bell Hangers' Hand-Book1893 |
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510 Marquette alarm and room amalgamated amperes annunciator armature automatic battery number battery wire bichromate binding post binoxide of manganese burglar alarm burner cells connected cells in series CHAPTER circuit is closed circuit is open connected in multiple connecting post copper wire current flows current strength dilute sulphuric acid disque Elect'n electric bells electric gas lighting electro-magnet electromotive force external circuit fire alarm floor key four cells galvanic cell galvanometer hotel annunciator hydrogen bubbles induction coil insulated internal resistance iron core joint resistance liquid magnet mercury metals multiple arc needle negative pole nitric acid number of ampere-turns Ohm's law ohms open circuit placed platinum polarization porous cell porous cup positive pole post number prisms push button ring room call run a wire sal-ammoniac screw soft iron spark spring sulphuric acid surface teries thermostat vibrating bell volts West wire for wires wire runs zinc plate zinc pole
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Side 13 - Instead of employing a porous cell to keep the two liquids separate, it is possible, where one of the liquids is heavier than the other, to arrange that the heavier liquid shall form a stratum at the bottom of the cell, the lighter floating upon it.
Side 105 - Its Descriptive Articles and Illustrations cover the new Electrical Inventions of America and Europe. It is replete with the Electrical News of the day. No Electric Lighting Company, no Dynamo Tender, no Lineman, no Stationary or Marine Engineer who wishes to fit himself to take charge of a dynamo or superintend an Electric Light Installation can afford to be without it. SUBSCRIPTION PRICE, ONLY $3.00 PER ANNUM.
Side 24 - The relative strengths of current in the two branches will be proportional to their conductances, ie inversely proportional to their resistances.• Thus, if r be a wire of 2 ohms resistance and...
Side 39 - It usually consists of a cylindrical knob of ivory or porcelain capable of moving loosely through a hole in a circular support of porcelain or wood, and which, when pressed, forces a platinum-tipped spring against a metal pin, and so makes electrical contact between the two parts of the interrupted...
Side 1 - No single cell fulfils all these conditions, however, and some cells are better for one purpose and some for another. Thus, for telegraphing through a long line of wire a considerable internal resistance in the battery is no great disadvantage ; while, for producing an electric light, much internal resistance is absolutely fatal. The electromotive-force of a battery depends on the materials of the cell, and on the number of cells linked together, and a high EMF can therefore be gained by choosing...
Side 24 - Figure 148), is used. The induction coil consists of a cylindrical bobbin having a central iron core surrounded by a short inner or "primary" coil of stout wire, and by an outer "secondary" coil made up of many thousand turns of very fine wire, which is carefully insulated between its different parts.
Side 24 - strength" of a magnet is the "strength" of its poles. The " strength " of a magnet pole must be measured by the magnetic force which it exerts.
Side 14 - Blue vitriol should be dropped into the jar as it is consumed, care being taken that it goes to the bottom and not on the zinc. The need of the blue vitriol is shown by the fading of the blue color, which should be kept at least as high as the top of the copper, but it should never reach the zinc. There should always be some bluestone crystals in the bottom of the jar. After the battery has been started...
Side 3 - As this solution would attack the zinc even when the circuit is open, the zinc plate is fixed to a rod by which it can be drawn up out of the solution when the cell is not being worked.
Side 24 - The joint resistance of the two branches between A and B will be less than the resistance of either branch singly, because the current has increased facilities for travel. In fact, the joint conductivity will be the sum of the two separate conductivities. Taking again the resistance of R = 10 ohms and R' — 20 ohms, the joint conductivity is 10T 20 20 BATTERY Mill III FIG.