Lessons in Electricity at the Royal Institution 1875-6D. Appleton, 1898 - 112 pàgines |
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Abbé Nollet amber balanced lath ball bring briskly cause coated with tin-foil comb cork cylinder deflagrated diverge Dutch metal earth ebonite elec electric attraction electric fluid ELECTRIC INDUCTION electric spark electrical machine electrified body electrophorus electroscope excited glass tube excited tube finger flannel fox's brush Franklin friction Frictional Electricity glass rod gutta-percha tube hair hand Hauksbee ignition inches long insulating stool JOHN TYNDALL knob leaf leaves Leyden jar lift loop Lord Mahon mercury negative electricity non-electrics obtained Otto von Guericke outer coating paper phial plate positive electricity prime conductor principles proved rendered repels rubbed repulsion resin returning stroke round rubbed glass tube rubbed gutta-percha self-repulsive sewing needle shellac shock shown in fig silk rubber stem Stephen Gray stick of sealing-wax straw stream strips strong stronger charge sulphur surface suspended touching tricity un-rubbed unelectric unelectrified warm glass wire
Passatges populars
Pàgina 46 - insulating plate, which on trial will be found negatively electrified. § 17. The Electrical Machine. An electrical machine consists of two principal parts; the insulator which is excited by friction, and the ' prime conductor.' The sulphur sphere of Otto von Guericke was, as already stated, the first electrical machine. The hand was the rubber, and indeed it long continued to be
Pàgina 1 - flannel, will pull the stick quite round. Abandon the wire loop ; place an egg in an egg-cup, and balance a long lath upon the egg, as shown in fig. 4. The lath, though it may be almost a plank, will
Pàgina 57 - finger, or a piece of gold which I hold in my hand, to the nail, I receive a shock which stuns my arms and shoulders.
Pàgina 16 - directly to the fundamental law of electric action, which is this :—Bodies charged with the same electricity repel each other, while bodies charged with opposite electricities attract each other. Positive repels positive, and attracts
Pàgina 49 - the negative electricity streams from the points against the excited glass, which then passes on neutralised to the next rubber, where it is again excited. Thus the prime conductor is charged, not by the direct communication to it of positive electricity, but by depriving it of its negative. If when the conductor is charged you bring the knuckle near it, the electricity passes from the
Pàgina 50 - conductor, which is thus neutralised almost as fast as it is charged. Flames and glowing embers act like points ; they also rapidly discharge electricity.
Pàgina 46 - the tube, test the carrot : it is positively electrified. And now for another experiment, not so easily made, but still certain to succeed if you are careful. Excite your glass rod, turn your needle away from it, and bring the rod near the other end of the carrot. What occurs? The positive electricity is now repelled to the point, from which it will stream into the air.
Pàgina 45 - found that he could deduce with great accuracy the sharpness of a point, from the charge which it imparted. He compared in this way the sharpness of various thorns, with that of a fine English sewing needle. The following is the result