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 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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