(a) For the telescope is in normal adjustment (i.e., when the final image is at infinity)? what is the separation between the objective lens and the eyepiece? - Physics

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Numerical

For the telescope is in normal adjustment (i.e., when the final image is at infinity)? what is the separation between the objective lens and the eyepiece?

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Solution

Focal length of the objective lens, fo = 140 cm

Focal length of the eyepiece, fe = 5 cm

In normal adjustment, the separation between the objective lens and the eyepiece = fo + fe = 140  + 5 = 145 cm

Concept: Optical Instruments: Telescope
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Chapter 9: Ray Optics and Optical Instruments - Exercise [Page 347]

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NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 9.29 (a) | Page 347
NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 35.1 | Page 349

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