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Two thin lenses have a combined power of...

Two thin lenses have a combined power of +9D.When they are separated by a distance of 20 cm, then their equivalent power becomes `+27/5` D. Their individual powers (in dioptre) are

A

4,5

B

3,6

C

2,7

D

1,8

Text Solution

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The correct Answer is:
B
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