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I need help with An upright object is placed at a distance of 40 cm in front of a convergent lens of focal length 20 cm. A convergent mirror of focal length 10 cm is placed at a distance of 60 cm on the other side of the lens. The position and size o

An upright object is placed at a distance of 40 cm in front of a convergent lens of focal length 20 cm. A convergent mirror of focal length 10 cm is placed at a distance of 60 cm on the other side of the lens. The position and size of the final image will be :

 

  • Option 1)

    20\; cm from the convergent mirror, same size as the object
     

  • Option 2)

    20\; cm from the convergent mirror, twice the size of the object

  • Option 3)

    40\; cm from the convergent mirror, same size as the object

     

  • Option 4)

    40\; cm from the convergent lens, same size of the object

 
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\rightarrow Total \; 3 \; process

(1) Refraction from lense

u =-40\; cm,\; \; f=+20\; cm

\Rightarrow V=+40\; cm, (Image\; I_{1})

and m_{1}=-1

(2) Reflection from mirror

u =-20\; cm,\; \; f=-10\; cm

\Rightarrow V=-20\; cm, (Image\; I_{2})

and  m_{2}=-1

(3) Refraction from lens

u =-40\; cm,\; \; f=+20\; cm

\Rightarrow V=+40\; cm, (Image\; I_{3})

and m_{3}=-1

m=m_{1}.m_{2}.m_{3}=-1

Final image is at 40\; cm from convergent lens and it has same size as object.


Option 1)

20\; cm from the convergent mirror, same size as the object
 

Option 2)

20\; cm from the convergent mirror, twice the size of the object

Option 3)

40\; cm from the convergent mirror, same size as the object

 

Option 4)

40\; cm from the convergent lens, same size of the object

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