If f1 = the focal length of a concave lens ; f2 = the focal length of a convex lens - Science - Light - Reflection and Refraction

Question

If f1 = the focal length of a concave lens ;
f2 = the focal length of a convex lens ; x = distance
between the two lenses ; and F = total focal length (combined
nature of the lenses) Prove that 1/F = 1/f1 +
1/f2​ - x/(f1*f2​)

Deepak Kumar · Accepted Answer

Dear Student ,

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If f1 = the focal length of a concave lens ; f2 = the focal length of a convex lens ; x = distance between the two lenses ; and F = total focal length (combined nature of the lenses) .Prove that 1/F = 1/f1 + 1/f2​ - x/(f1*f2​)

If f₁ = the focal length of a concave lens ; f₂ = the focal length of a convex lens ; x = distance between the two lenses ; and F = total focal length (combined nature of the lenses) .Prove that 1/F = 1/f₁ + 1/f₂ - x/(f₁*f₂)