# When two lenses of focal length +10cm and -10cm are placed in contact then find the net power?

2
by anujNayar

2015-03-25T22:19:15+05:30

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When two lenses of focal length f₁ and f₂ are kept in contact, the net power is given by

f₁ = 10 cm
f₂ = -10 cm

2015-03-26T05:45:38+05:30

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Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Net Power P = 1/f1 + 1/f2
= 1/10  + [1/-10]
= 1/10-1/10
= 0
Hence the net power of 2 lenses when they placed in contact = 0