Physics by Experiment: An Elementary Text-book for the Use of Schools

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Maynard & Company, 1891 - 320 ページ
 

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90 ページ - The resistance which is opposed to a pump rod in raising water, is ~equal to the weight of a column of water whose base is the area of the piston, and...
47 ページ - Gravitation all we know is, that it is a force of attraction operating between all the particles of matter in the exact measure which was ascertained by Newton, — that is — "directly as the mass, and inversely as the square of the distance.
186 ページ - ... which struck the water, that is to say the angle of reflection will be equal to the angle of incidence.
151 ページ - ... sound is transmitted more slowly. In liquids, which are always heavier than air, you would naturally think that sound would travel more slowly than in air, but this is not true. Liquids are less compressible than gases and this causes the speed with which sound is transmitted in them to be increased. In water sound travels about four times as fast as in air. What Are the Properties of Sound? Sounds differ from each other by the extent to which they possess three qualities, namely ; intensity,...
159 ページ - ... range of four octaves, but also in the special quality of tone which is peculiar to each class of voice, and which may be referred to the corresponding structure of the larynx. The difference in the pitch of tones is due in the first place to the number of vibrations performed by the vocal chords in a given time ; the greater the number of vibrations, the higher is the tone produced. While E is produced by 80 vibrations in the second, 1024 vibrations are required in the same period to give c'".
112 ページ - This law states that the volume of a gas is inversely proportional to the pressure exerted upon it; therefore, as we ascend and the pressure outside the aircraft decreases, the air expands.
263 ページ - ... atmospheric system flows in upon the centre in a spiral course. This rotatory peculiarity is common to all storms in the northern hemisphere that have yet been examined. In the southern hemisphere, a rotatory motion is also observed round the centre of storms, but it takes place in a contrary direction, or in the direction of the motion of the hands of a watch, instead of contrary to that direction, as obtains north of the equator. Professor Taylor has the merit of having first applied Dove's...
133 ページ - It overcomes the attractive forces that tend to hold the molecules of a substance together, and thus changes it from a solid to a liquid or from a liquid to a gas, according to the state it was in when the heat was applied.
254 ページ - The strength of the current varies directly as the electromotive force and inversely as the resistance of the circuit, or — /= E/R, or R - Ell, or E = IR.
72 ページ - The time of vibration varies directly as the square root of the length of the pendulum.

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