 If the force with which it strikes the air below it, is equal to the weight of its body, then the re-action of the air upwards is likewise equal to it, and the bird being acted upon by two equal forces in contrary directions, will rest between them. If...  Of mechanics and astronomy - Page 28by Jeremiah Joyce - 1829Full view - About this book
 | William Enfield - Astronomy - 1811 - 476 pages
...For if the force with which it strikes the air below it, is equal to this weight, then the re-action of the air upwards is likewise equal to it ; and the...its weight, then it will sink with the difference. EXP. Let a clay ball in motion strike another equal to it at rest : The striking body will lose half... | |
 | Jeremiah Joyce - Science - 1815 - 268 pages
...force with which it strikes the air below it is equal to the weight of its body, then the re-action of the air upwards is likewise equal to it; and the bird, being acted upon by twoequalforces in contrary directions, will rest between them. If the force of the stroke is greater... | |
 | Levi Washburn Leonard - New Hampshire - 1827 - 398 pages
...force with which it strikes the air below it, is equal to the weight of its body, then the re-action of the air upwards is likewise equal to it, and the...weight, the bird will rise with the difference of these twa forces ; and if the stroke be less than its weight, then it will sink with the difference. In the... | |
 | John Ayrton Paris - Science - 1827 - 332 pages
...with a force which is equal to its weight, then must there be a reaction of the air, upwards, exactly equal to it ; and the bird, being acted upon by two equal forces, in opposite directions, will, necessarily, rest between them." ' " That is clear enough ; but the bird... | |
 | Levi Washburn Leonard - New Hampshire - 1828 - 362 pages
...force with which it strikes the air below it, is equal to the weight of its body, then the re-action of the air upwards is likewise equal to it, and the...its weight, then it will sink with the difference. In the act of rowing, the water is struck with the oars, in a direction opposite to that in which the... | |
 | Levi Washburn Leonard - Science - 1830 - 350 pages
...force with which it strikes the air below it, is. equal to the weight of its body, then the re-action of the air upwards is likewise equal to it, and the...its weight, then it will sink with the difference. In the act of rowing, the water is struck witti the oars, in a direction opposite to that in which... | |
 | William Enfield - Astronomy - 1832 - 282 pages
...Por if the force with which it strikes the air below it, is equal to this weight, then the re-action of the air upwards is likewise equal to it ; and the...will rest between them. If the force of the stroke be greater than its weight, the bird will rise with the difference of these two forces : And if the... | |
 | Levi Washburn Leonard - Civilization - 1833 - 370 pages
...force with which it strikes the air below it, is 'equal to the weight of its body, then the re-action of the air upwards is likewise equal to it, and the...between them. If the force of the stroke is greater than it* weight, the bird will rise with the difference of these two forces ; and if the stroke be less... | |
 | John Lauris Blake - Encyclopedias and dictionaries - 1834 - 1028 pages
...force with which it strikes the air below it, is equal to the weight of its body, then the reaction of the air upwards is likewise equal to it, and the...force of the stroke is greater than its weight, the hirtl will rise with the difference of these two forces ; and if the stroke be less than its weight,... | |
 | Jeremiah Joyce - Physical sciences - 1838 - 398 pages
...to it ; and the hird, heing acted upon hy two equal forces in contrary directions, will rest hetween them. If the force of the stroke is greater than its weight, the hird will rise with the difference of these two forces ; and if the stroke he less than its weight,... | |
| |
