Where should an object be placed from a converging lens of focal length 20 cm, so as to obtain a real image of magnification 2?A. 50 cmB. 30 cmC. `-50 cm`D. `30 cm`

Where should an object be placed from a converging lens of focal lengt

1.	Where should an object be placed from a converging lens of focal length 20 cm, so as to obtain a real image of magnification 2?A. 50 cmB. 30 cmC. `-50 cm`D. `30 cm`
Answer» Correct Answer - D (d) For real image from converging lens, m=-2 `therefore` Magnification ,m`=f/(f+u)rArr-2=f/(u+f)=20/(u+20)` `rArr` u=-30 cm

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Where should an object be placed from a converging lens of focal length 20 cm, so as to obtain a real image of magnification 2?A. 50 cmB. 30 cmC. `-50 cm`D. `30 cm`

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