The Practice of Navigation: And Nautical AstronomyJ. D. Potter, 1882 - 910 sider |
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Resultat 1-5 av 60
Side 40
... tangent to the circle . Take any point D in AT , and join CD ; then since CAD is a right angle , CDA is less than a right angle ( No. 127 ) , and therefore CD is greater than CA ( No. 128 ) or falls beyond the circum- ference , that is ...
... tangent to the circle . Take any point D in AT , and join CD ; then since CAD is a right angle , CDA is less than a right angle ( No. 127 ) , and therefore CD is greater than CA ( No. 128 ) or falls beyond the circum- ference , that is ...
Side 45
... tangent is 0 ; when the arc is small , the tangent and sine may be taken for each other , and for the arc . When the arc is 90 ° , the tangent is infinitely great . The tangent is less than the radius , according as the angle is less or ...
... tangent is 0 ; when the arc is small , the tangent and sine may be taken for each other , and for the arc . When the arc is 90 ° , the tangent is infinitely great . The tangent is less than the radius , according as the angle is less or ...
Side 46
... tangent of 45 ° is equal to the radius . Let PCA ( fig . No. 160 ) be 45 ° , then CTA is also 45 ° ( No. 127 ) , hence the triangle is isosceles and the sides CA , AT are equal . P COR . Hence also , by similar triangles , CNN P , or ...
... tangent of 45 ° is equal to the radius . Let PCA ( fig . No. 160 ) be 45 ° , then CTA is also 45 ° ( No. 127 ) , hence the triangle is isosceles and the sides CA , AT are equal . P COR . Hence also , by similar triangles , CNN P , or ...
Side 161
... tangent - screw , clamp the index , and make the contact perfect by turning the screw , some further remarks on which will be made in the proper places . The tangent - screw should be kept nearly middled when not in use . 490. To take ...
... tangent - screw , clamp the index , and make the contact perfect by turning the screw , some further remarks on which will be made in the proper places . The tangent - screw should be kept nearly middled when not in use . 490. To take ...
Side 164
... tangent - screw right and left alternately , in making successive con- tacts , by which a partial compensation is obtained . This source of discrepancy is , however , effectually removed by taking all observa- tions , including that for ...
... tangent - screw right and left alternately , in making successive con- tacts , by which a partial compensation is obtained . This source of discrepancy is , however , effectually removed by taking all observa- tions , including that for ...
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The Practice of Navigation and Nautical Astronomy Henry Raper Ingen forhåndsvisning tilgjengelig - 2018 |
The Practice of Navigation and Nautical Astronomy (Classic Reprint) Henry Raper Ingen forhåndsvisning tilgjengelig - 2017 |
The Practice of Navigation and Nautical Astronomy Henry Raper Ingen forhåndsvisning tilgjengelig - 2018 |
Vanlige uttrykk og setninger
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Populære avsnitt
Side 41 - The angle in a semicircle is a right angle ; the angle in a segment greater than a semicircle is less than a right angle; and the angle in a segment less than a semicircle is greater than a right angle.
Side 19 - The characteristic of a number less than 1 is found by subtracting from 9 the number of ciphers between the decimal point and the first significant digit, and writing — 10 after the result.
Side 38 - A parallelogram is a four.sided figure, of which the opposite sides are parallel; and the diameter is the straight line joining two of its opposite angles.
Side vii - This is the more important, as very indistinct and erroneous notions prevail among practical persons on the subject of accuracy of computation ; and much time is, in consequence, often lost in computing to a degree of precision wholly inconsistent with that of the elements themselves. The mere habit of working invariably to a useless precision, while it can never advance the computer's knowledge of the subject, has the unfavourable tendency of deceiving those who are not aware of the true nature...
Side 147 - For the same body the semidiameter varies with the distance; thus, the difference of the sun's semidiameter at different times of the year is due to the change of the earth's distance from the sun; and similarly for the moon and the planets.
Side 22 - A CIRCLE is a figure bounded by a curve line called the circumference,* of which every point is at the same distance from a point within, called the centre. Thus, ABD is a circle, and C the centre.
Side 43 - ... section shall be parallel to the remaining side of the triangle. Let DE be drawn parallel to BC, one of the sides of the triangle ABC: then BD shall be to DA, as CE to EA. Join BE, CD; then the triangle BDE is equal...
Side 37 - ... the three interior angles of' a triangle are together equal to two right angles.
Side 39 - Hence it is plain that triangles on the same or equal bases, and between the same parallels, are equal, seeing (by cor.
Side 105 - The distance between two points on the surface of a sphere is the length of the minor arc of a great circle between them.