Find two positions of an object, placed in front of a concave mirror o – InterviewSolution

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1.	Find two positions of an object, placed in front of a concave mirror of focal length 15cm, so that the image formed is 3 times the size of the object.
Answer» f = 15 cm m =3 i) `m=(-upsilon)/(u)=(f)/(f-u)` `3=(15)/(15-u)` `45-3u=15` 3u = 30 u = 10 cm. ii) `m=(f)/(u-f)` `3=(15)/(u-15)` `3u-45=15` 3u = 60 u = 20 cm.

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