A) 40 cm from the convergent mirror, same size as the object
B) 20 cm from the convergent mirror, same size as the object
C) 20 cm from the convergent mirror, twice the size of the object
D) 40 cm from the convergent lens, twice the size of the object
Correct Answer: B
Solution :
Note : There will be 3 phenomenon (i) Refraction from lens (ii) Reflection from mirror (iii) Refraction from lens After these phenomena. Image will be on object and will have same size. None of the option depicts so this question is Bonus 1st refraction \[u=40cm;f=+20cm\] \[\Rightarrow \]\[\text{v}=+40cm\,(image\,{{I}_{1}})\] and\[{{m}_{1}}=-1\]for reflection \[u=-20cm;f=-10cm\] \[\Rightarrow \text{v}=-20cm\,(image\,{{I}_{2}})\] and \[{{m}_{2}}=-1\] 2nd refraction \[u=40cm;\text{ }f=+20cm\] \[\text{v}=+40cm\left( \text{image }{{I}_{3}} \right)\] and \[{{m}_{3}}=-1\] Total magnification\[={{m}_{1}}\times {{m}_{2}}\times {{m}_{3}}=1\]and final image is formed at distance 40cm from convergent lens and is of same size as the objectYou need to login to perform this action.
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