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Two lenses of power +12 and -2 diopters ...

Two lenses of power `+12` and `-2` diopters are placed in contact. The combined focal length of the combination will be

A

`8.33 cm`

B

`1.66cm`

C

`12.5 cm`

D

`10 cm`

Text Solution

Verified by Experts

The correct Answer is:
D
`P=P_(1)+P_(2)`
`=+12-2=10D`
Now `F=(1)/(P)=(1)/(10)m=10cm`.
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