What is the Height of the Final Image of the Tower If It is Formed at 25 Cm? - Physics

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Numerical

What is the height of the final image of the tower if it is formed at 25 cm?

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Solution

Focal length of the objective lens, fo = 140 cm

Focal length of the eyepiece, fe = 5 cm

Image is formed at a distance, d = 25 cm

The magnification of the eyepiece is given by the relation:

`"m" = 1 + "d"/"f"_"e"`

= `1 + 25/5`

= 1 + 5

= 6

Height of the final image = mh2 = 6 × 4.7 = 28.2 cm

Hence, the height of the final image of the tower is 28.2 cm.

Concept: Optical Instruments: the Eye
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Chapter 9: Ray Optics and Optical Instruments - Exercise [Page 348]

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NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 9.29 (c) | Page 348
NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 35.3 | Page 349

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