Q 12-09-030NEETJEE MainMedium
An object is $15$ cm from a convex lens of focal length $10$ cm. The magnification of the image is
Answer: (A) $-2$
$\dfrac{1}{v} = \dfrac{1}{10} - \dfrac{1}{15} = \dfrac{1}{30}$, so $v = 30$ cm and $m = \dfrac{v}{u} = \dfrac{30}{-15} = -2$ (real, inverted, twice the size).
Solution by Sreeraj P, M.Sc Physics