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A convex lens of 40 cm focal length is c...

A convex lens of 40 cm focal length is combined with a concave lens of focal length 25 cm. The power of combination is

A

`-1.5 D`

B

`-6.5 D`

C

`+ 6.6 D`

D

`+ 6.5 D`

Text Solution

Verified by Experts

The correct Answer is:
A, D
`P=P_(1)+P_(2)=(1)/(f_(1))=(100)/(40)+(100)/(-25)=-1.5D`
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