MCQ
In displacement method, convex lens forms a real image of an object for its two different positions. If heights of the images in two cases be $24 \,cm$ and $6 \,cm$, then the height of the object is ........ $cm$
- A$3$
- B$36$
- C$6$
- ✓$12$
✓
Answer
Correct option: D.
$12$
d
(d)
(d)
In displacement method
$m_1 m_2=1$
$\frac{h_1}{h} \times \frac{h_2}{h}=1$
$h=\sqrt{h_1 h_2}$
$h=\sqrt{24 \times 6}$
$h=12 \,cm$
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