A senior citizen wears bifocals (Fig. 25.23) in which the top half of the lens has a focal length of – 0.850 and the bottom half of the lens has a focal length of + 0.500. What are this person’s near point and far point?
Answer to relevant QuestionsA certain man has a far point of 150 cm. (a) What power must contact lenses have to allow him to see distant objects clearly? (b) If he is able to read a newspaper at 25 cm while wearing his contacts, is his near point ...An object is placed 10 cm in front of a converging lens with a focal length of 18 cm. What are (a) The lateral magnification and (b) The angular magnification? If a magnifying glass gives an angular magnification of 1.5 x when viewed with relaxed eyes, what is the power of the lens? A – 150 x microscope has an eyepiece whose focal length is 4.4 cm. If the distance between the lenses is 20 cm, find the focal length of the objective. A terrestrial telescope has three lenses: an objective, an erecting lens, and an eyepiece. (a) Does the erecting lens (1) increase the magnification, (2) increase the physical length of the telescope, (3) decrease the ...
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