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A person has near point at 60 cm . The f...

A person has near point at 60 cm . The focal length of spectacles lenses to read at 22 cm having glasses separated 2 cm from eyes is

A

40cm

B

10 cm

C

20 cm

D

30 cm

Text Solution

Verified by Experts

The correct Answer is:
The option D is correct.
Distance of the object from lens , u=-(22-2)=-20cm image distance , v=-60 cm
`1/f=1/v-1/u=-1/(60)+1/(20)=1/(30)`
Hence , f=30 cm
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