When an object is placed 40 cm away from a spherical mirror an image of magnification 2 1 is produced. To obtain an image with magnification of 3 1 , the object is to be moved :

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When an object is placed 40 cm away from a spherical mirror an image of magnification 2 1 ​ is produced. To obtain an image with magnification of 3 1 ​ , the object is to be moved :

TestHub · Accepted Answer

​ m = 2 1 ​ = f − u f ​ 2 1 ​ = f − ( − 40 ) f ​ f + 40 = 2 f ⇒ f = 40 cm now m = 3 1 ​ = 40 − u 40 ​ 40 − u = 120 ⇒ u = − 80 ​

Physics - Geometrical Optics Question with Solution | TestHub

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