NCERT Exercise 9.2 - Ray Optics and Optical Instruments
Question: A 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. Give the location of the image and the magnification. Describe what happens as the needle is moved farther from the mirror.
Answer: **NCERT answer:** v = 6.7 cm. Magnification = 5/9, i.e., the size of the image is 2.5 cm. As u → ¥; v → f (but never beyond) while m → 0.
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