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Ray Optics — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsRay Optics1 Mark
MCQ
A convex lens forms a real image of an object for its two different positions on a screen. If height of the image in both the cases be $8\  \mathrm{cm}$ and $2 \mathrm{~cm}$, then height of the object is
  • A
    $16 \mathrm{~cm}$
  • B
    $8 \mathrm{~cm}$
  • ✓
    $4 \mathrm{~cm}$
  • D
    $2 \mathrm{~cm}$
✓

Answer

Correct option: C.
$4 \mathrm{~cm}$
$O=\sqrt{I_1 I_2}=\sqrt{8 \times 2}=4 \mathrm{~cm}$

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