 Parallels, which are imaginary circles parallel with the equator, determine latitude. The length of a degree of longitude varies as the cosine of the latitude. At the equator a degree is 69.171 statute miles; this is gradually reduced toward the poles.  Elements of Trigonometry, Plane and Spherical - Page 62by Edward Olney - 1872 - 201 pagesFull view - About this book
 | 1834 - 578 pages
...cosine of the latitude ; and as the degree at the equator and the radius of the earth are invariable, the length of a degree of longitude varies as the cosine of the latitude. CHAPTER VIII. Oblate-Spheroidal Figure of the Earth — Cause of thit Figure — Centrifugal Force.... | |
 | Archibald Hastie DICK - Mathematical geography - 1863 - 264 pages
...360°, therefore the lengths of the degrees in each must diminish as they approach the poles. (78.) The length of a degree of longitude varies as the cosine of the latitude. Hence, if we know the latitude (b) of any place and the radius of the earth (E), we may calculate the... | |
 | Edward Olney - Trigonometry - 1885 - 222 pages
...time, 51-1 miles east or west on this parallel is equivalent to 4 minutes difference in timeQUERY — How does it appear from the above solution that the...distance of a planet from the earth at any particular timeSOLUT1ON — To render the problem as simple as possible, we will suppose two observatories on... | |
 | Edward Olney - Geometry - 1872 - 472 pages
...in time, 51.1 Q. F1o. 22. miles cast or west on this parallel is equivalent to 4 minutes ditference in time. QUERY. — How does it appear from the above...suppose two observatories on the same meridian, at N,and N'; and that when the planet P is on the same meridian, the angles ZNP, and Z'N'P (the zenith... | |
 | Edward Olney - Geometry - 1872 - 562 pages
...fiu. is. miles east or west on this parallel is equivalent to 4 minutes difference in time. QUKKT.— How does it appear from the above solution that the...of longitude varies as the cosine of the latitude f 2. To find the distance of a planet from the earth at any particular time. SOLUTION — To render... | |
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