Question

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27. An object is placed at a distance of 75 cm from a
screen. Two positions of a convex lens of focal
length 12 cm placed so as to obtain a real image
[f= P2 x 2
(1) 60 cm, 15 cm (2) 50 cm, 25 cm UD
(3) 45 cm, 35 cm (4) 70 cm, 5 cm
28. Two plano-concave lenses of glass of refractive
index 1.5 have radii of curvature of 20 cm and 30
cm. They are placed in contact with curved​

Answer 1

Explanation:

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