Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial. The combination is equivalent to a single lens of power - VgyanHub

Question:

Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial. The combination is equivalent to a single lens of power

Options :

(a) f1+f2
(b) f1 f2/f1+f2
(c) 1/2(f1+f2)
(d) f1+f2/f1 f2

Answer :

(d) f₁+f₂/f₁ f₂

Answer Steps :

step 1

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