A Compendium of Natural Philosophy: Adapted to the Use of the General Reader, and of Schools and Academies : to which is Now Added a Supplement Containing Instructions to Young Experimenters, with a Copious List of Experiments, Accompanied by Minute Directions for Performing ThemS. Babcock, 1846 - 420 σελίδες |
Άλλες εκδόσεις - Προβολή όλων
Συχνά εμφανιζόμενοι όροι και φράσεις
angle apparatus applied atmosphere attraction axis axle ball beam body center of gravity centrifugal force charge colors column concave concave lens condensed consequently convex lens cylinder depth descend diameter diminished direction earth effect elastic electricity electrified electrometer equal example exhibited experiments fall feet figure fluid focal distance focus force friction fulcrum glass greater Hence horizontal inches inclined plane increased instrument insulated iron knob lenses less lever Leyden Jar light machine magnet magnifying mechanical mechanical advantage microscope mirror motion move Natural Philosophy needle object opposite orifice parallel passing pendulum perpendicular piston placed plate pole portion pressure prime conductor principle produced pulley pump quantity of water rays reflexion refracting resistance rest screw sewing needle side sound space spark specific gravity spherical aberration steam substances supposed surface telescope thread tion tricity tube valve velocity vessel vibrations weight wheel window shutter
Δημοφιλή αποσπάσματα
Σελίδα 183 - In the present perfect state of the engine it appears a thing almost endowed with intelligence. It regulates with perfect accuracy and uniformity the number of its strokes in a given time, counting or recording them, moreover, to tell how much work it has done, as a clock records the beats of its pendulum ; it regulates the quantity of steam admitted to work; the briskness of the fire; the supply of water to the boiler ; the supply of coals to the fire ; it opens and shuts its valves with absolute...
Σελίδα 91 - The pulley is a small wheel, movable about its axis by means of a cord, which passes over it. When the axis of a pulley is fixed, the pulley only changes the direction of the power ; if movable pulleys are used, an equilibrium is produced, when the power is to the weight, as one to the number of ropes applied to them.
Σελίδα 183 - Its aliment is coal, wood, charcoal, or other combustible ; it consumes none while idle ; it never tires, and wants no sleep ; it is not subject to malady when originally well made, and only refuses to work when worn out with age ; it is equally active in all climates, and will do work of any kind ; it is a water-pumper, a miner, a sailor, a cotton-spinner, a weaver, a blacksmith, a miller, &c.
Σελίδα 49 - If three forces acting at a point are in equilibrium they can be represented in magnitude and direction by the three sides of a triangle taken in order.
Σελίδα 102 - In many cases, the utility of the wedge depends on that which is entirely omitted in its theory, viz., the friction which arises between its surface and the substance which it divides. This is the case when pins, bolts, or nails, are used for binding the parts of structures together ; in which case, were it not for the friction, they would recoil from their places, and fail to produce the desired effect. Even when the wedge is used as a mechanical engine, the presence of friction is absolutely indispensable...
Σελίδα 141 - A very slight declivity suffices to give the running motion to water. Three inches per mile, in a smooth straight channel, gives a velocity of about three miles per hour. The Ganges, which gathers th'e waters of the Himalaya mountains, the loftiest in the world...
Σελίδα 64 - ... different degrees of ramming, nor by firing the charge of powder in different parts of it; but that a very great difference in the velocity arises from a small degree in the windage.^ Indeed, with the usual established windage only, viz. about ^ of the calibre, no less than between | and { of the powder escapes and is lost, and as the balls are often smaller than...
Σελίδα 16 - Force is any cause which moves or tends to move a body, or which changes or tends to change its motion.
Σελίδα 78 - As the diameter of. the axle is to the diameter of the wheel, so is the power applied to the wheel, to the weight suspended on the axle.
Σελίδα 214 - He says that he felt himself struck in his arms, shoulders, and breast, so that he lost his breath, and it was two days before he recovered from the effects of the blow and the fright. He would not, he adds, take a second shock for the whole kingdom of France.