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A bulb is placed at a depth of 2sqrt7cm ...

A bulb is placed at a depth of `2sqrt7cm` in water and a floating opaque disc is placed over the bulb so that the bulb is not visible from the surface. What is the minimum diameter of the disc?

A

42 m

B

6 m

C

`2sqrt7` m

D

12 m

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The correct Answer is:
D
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AAKASH INSTITUTE-RAY OPTICS AND OPTICAL INSTRUMENTS-ASSIGNMENT (SECTION - C)
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