For normal adjustment, length of astronomical telescope is:
Correct answer: A. f₀ + fₑ
- A. f₀ + fₑ
- B. f₀ - fₑ:
- C. f₀/ fₑ:
- D. fₑ/f₀:
Explanation
Explanation: For normal adjustment of an astronomical telescope, the final image is formed at infinity. The relationship for the length of the telescope (L) is given by L=f0 +fe , where f0 is the focal length of the objective lens and fe is the focal length of the eyepiece.
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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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