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An eye specialist prescribes spectacles ...

An eye specialist prescribes spectacles having combination of convex lens of focal length 40cm in contact with a concave lens of focal length 25cm. The power of this lens combination in diopters is

A

`+ 1.5`

B

`- 1.5`

C

`+ 6.67`

D

`- 6.67`

Text Solution

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The correct Answer is:
b
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