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Question
Write the three characteristics of the image formed by a convex lens of focal length 20 cm for the object at distance (i) 10 cm, (ii) 30 cm, (iii) 40 cm, (iv) 60 cm from the lens.
Solution
(i) For the object at distance 10 cm, the image is virtual, upright, and enlarged.
(ii) For the object at distance 30 cm, the image is real, inverted, and enlarged.
(iii) For the object at distance 40 cm, the image is real, inverted, and the same size.
(iv) For the object at distance 60 cm, the image is real, inverted, and diminished.
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