| Harry Houdini Collection (Library of Congress) - Technology - 1894
...fact that any distortion at the surface of a mirror affects the direction of a ray of light three time **as much as the same distortion would do at the surface...the magnifying power will be a hundred and twenty** diameters — ie, the disk of a planet, for instance, will be enlarged a hundred and twenty times along... | |
| William Henry Chandler - Encyclopedias and dictionaries - 1898
...and has its axis parallel to that of the large one. Roughly, the magnifying power of a telescope is **the ratio of the focal length of the objective to that of the** eyepiece. Roger Bacon understood the principles on which the telescope depends ab.1250; so perhaps... | |
| Charles Riborg Mann, George Ransom Twiss - Physics - 1905 - 449 pages
...objective, and L'F is that of the eyepiece; so we see that the magnification of the telescope is determined **by the ratio of the focal length of the objective to that of the** eyepiece. Therefore, if we wish to make telescopes that shall have large magnifying powers, we must... | |
| Silas Ellsworth Coleman - Physics - 1906 - 439 pages
...proportion, we have angle aEb : angle a Ob = F\f 3*9 (approximately) ; that is, the magnifying power **is measured by the ratio of the focal length of the objective to** the focal length of the eyepiece. The objective is of large diameter in order to receive as much light... | |
| Silas Ellsworth Coleman - Physics - 1908 - 264 pages
...the difference between the focal lengths of the lenses. 2. Compare the estimated magnification with **the ratio of the focal length of the objective to that of the eye lens.** 3. Copy Figure 82 and answer the questions under 4 of the discussion at the end of the preceding experiment.... | |
| Charles Elijah Linebarger - Physics - 1910 - 471 pages
...gives a total magnification equal to — x - =J— • The 1nag25 // nifying power of an astronomical **telescope is measured by the ratio of the focal length of the objective to** the focal length of the eyepiece. A high magnifying power, then, is secured by using an objective of... | |
| Charles Elijah Linebarger - Experiments - 1911 - 175 pages
...power of a telescope is equal to (a) the ratio of the size of the image to that of the object; (6) **the ratio of the focal length of the objective to that of the eye** piece. How do the values of the magnifying power measured by the two methods compare? TABULATION /.... | |
| R.A. Houstoun - 1919
...the eyepiece ; then by the graphical construction we find that a virtual image of ME is formed at HG. **The magnifying power of the telescope is measured by the ratio of the** angle subtended at the eye by the image in the telescope to the angle subtended by the distant object... | |
| Encyclopedias and dictionaries - 1920
...France about 1850. The magnifying power of telescopes is usually expressed in diameters and is indicated **by the ratio of the focal length of the objective to that of the** combination of lenses forming the eye-piece. For example, the Lick telescope has a focal length of... | |
| United States. Army. Ordnance Dept. War Department - 1921 - 307 pages
...ratio of the diameter of the entrance pupil to that of the exit pupil, and these in turn are determined **by the ratio of the focal length of the objective to that of the** eyepiece. Another method for ascertaining the linear magnifying power is to measure the angular vergency... | |
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