In viewing through a magnifying glass, one usually positions one’s eyes very close to the lens. Does angular magnification change if the eye is moved back? - Physics

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Short Note

In viewing through a magnifying glass, one usually positions one’s eyes very close to the lens. Does angular magnification change if the eye is moved back?

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Solution

Yes, the angular magnification changes. When the distance between the eye and a magnifying glass is increased, the angular magnification decreases a little. This is because the angle subtended at the eye is slightly less than the angle subtended at the lens. Image distance does not have any effect on angular magnification.

Concept: Optical Instruments: the Eye
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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 9.26 (b) | Page 347
NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 32.2 | Page 349

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