the near point of a hypermetropic person is 75cm.Calculate the focal length and the power of the lens in his spectacles

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Solution

Dear Student,
u=-25 cm(near point),v=-75 cm(v is negative),f=?
1/f=1/v-1/u
use this ,
1/f=2/75
so as power should be in metres( * by 100)
1/f=2/75*100=8/3=+2.6
d=+2.6 dioptre

Regards

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the near point of a hypermetropic person is 75cm.Calculate the focal length and the power of the lens in his spectacles

Dear Student, u=-25 cm(near point),v=-75 cm(v is negative),f=? 1/f=1/v-1/u use this , 1/f=2/75 so as power should be in metres( * by 100) 1/f=2/75*100=8/3=+2.6 d=+2.6 dioptre Regards

Dear Student,
u=-25 cm(near point),v=-75 cm(v is negative),f=?
1/f=1/v-1/u
use this ,
1/f=2/75
so as power should be in metres( * by 100)
1/f=2/75*100=8/3=+2.6
d=+2.6 dioptre

Regards