Elementary PhysicsLongmans, Green, 1892 - 248 pàgines |
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angle attract bar magnet battery beaker becomes boiling boiling-point brass called candle cardboard cell centre charged coloured concave condensation conductor connected convex lens cooling copper wire cork cylinder Daniell cell disc distance divergence earth electricity electrified body electromotive force electroscope equal expansion experiment Explain Fahrenheit flame flannel flask focal length focus glass rod glass tube Grove cell hole inches induction inserted insulated iron filings isoclinic lines latent heat Leyden jar light liquid magnetised melt mercury metal mirror move N-seeking pole negative electrification object obtained paper particles passes piece pith ball plate platinum positive electrification potential prism proof-plane rarefaction rays reflected refracted removed repelled rubbed screen sealing-wax sheet shellac soft iron sound sound-waves specific heat sphere steam steel string sulphate sulphuric acid surface suspended temperature thermometer tinfoil touch vapour vibrations voltaic vulcanite wave zinc
Passatges populars
Pàgina 52 - Remove for a single summer-night the aqueous vapour from the air which overspreads this country, and you would assuredly destroy every plant capable of being destroyed by a freezing temperature. The warmth of our fields and gardens would pour itself unrequited into space, and the sun -would rise upon an island held fast in the iron grip of frost.
Pàgina 40 - The rim of the balance wheel of a watch is made up of rings of two different metals, one outside the other, and is cut at two points ; explain how it is possible for the rate of the watch to be the same in hot and cold weather.
Pàgina 223 - The current from a voltaic battery is passed at the same time through a thin wire and through dilute sulphuric acid, connected in series. What will happen to the wire and to the dilute acid, and what change (if any) will be produced in each case by reversing the battery connections, so as to alter the direction of the current through the wire and liquid ? 6.
Pàgina 232 - Two copper wires connected, one with the zinc end and the other with the platinum end of a voltaic battery, but not connected with each other, are brought near a piece of sealing-wax that has been rubbed with flannel, and then nicely balanced on a point. Would the wires differ in any way in their action upon the sealing-wax ? If so, how and why ? 6.
Pàgina 175 - A pith ball is suspended from a metal stand by a fine thread. If you have a strongly electrified glass rod, how can you find out whether the thread is a conductor or a non-conductor of electricity ? 3.
Pàgina 232 - An insulated copper wire is wrapped round a glass tube, AB, from end to end, and a current is sent through it, which, to an observer looking at the end A, appears to go round in the same direction as the hands of a watch. A rod of soft iron is held (i) inside the tube and (2) outside, but parallel to the tube.
Pàgina 182 - If an electrified piece of metal is made to touch a 'gold-leaf electroscope, the leaves separate and, on taking the metal away, they remain separate. But if the electrified metal is only brought near to the electroscope, and then taken away, the leaves separate when the electrified metal is near, but fall together when it is taken away.
Pàgina 199 - ... 14. A piece of dry brown paper, laid on a warm metal tray, is rubbed with catskin. The tray is then placed on a dry glass tumbler, and the brown paper is removed. Why can you now get a spark on bringing your knuckle near the tray ? 15.