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 $8 cm$ and $2 cm,$ then height of the object is........$cm$
- A$16$
- B$8$
- ✓$4 $
- D$2 $
✓
Answer
Correct option: C.
$4 $
c
(c) $O = \sqrt {{I_1}{I_2}} = \sqrt {8 \times 2} = 4cm$
(c) $O = \sqrt {{I_1}{I_2}} = \sqrt {8 \times 2} = 4cm$
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