Two identical thin Plano convex lenses of refractive index n are silve – McqOptions

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1.	Two identical thin Plano convex lenses of refractive index n are silvered, one on the plane side and the other on the convex side. The ratio of their focal lengths is
A.	\[\frac{n}{n-1}\]
B.	\[\frac{n-1}{n}\]
C.	\[\frac{n+1}{n}\]
D.	\[n\]
Answer» B. \[\frac{n-1}{n}\]

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