Magnification of the astronomical telescope is_____________?
Correct answer: B. fo/fe
- A. fo+fe
- B. fo/fe
- C. fe/fo
- D. (1+fo/fe)L/fo
Explanation
For an astronomical telescope in normal adjustment, the objective forms an image at its focal plane and the eyepiece magnifies it, giving angular magnification M = fo/fe, where fo and fe are the objective and eyepiece focal lengths. The likely mistake is choosing c, fe/fo, which reverses the roles of the objective and eyepiece.
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About Optics
Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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