![Two plano - convex lenses of focal lengths f and 2 f are coaxially separated so that the spherical aberration is minimized. The effective focal length of the combination is : Two plano - convex lenses of focal lengths f and 2 f are coaxially separated so that the spherical aberration is minimized. The effective focal length of the combination is :](https://dwes9vv9u0550.cloudfront.net/images/6593633/af7891d2-ed66-4bf0-a96b-559af6d135d4.jpg)
Two plano - convex lenses of focal lengths f and 2 f are coaxially separated so that the spherical aberration is minimized. The effective focal length of the combination is :
![Consider a coaxial system of two thin convex lenses of focal length f each separated by a distan... - YouTube Consider a coaxial system of two thin convex lenses of focal length f each separated by a distan... - YouTube](https://i.ytimg.com/vi/fpCpJodJxTk/maxresdefault.jpg)
Consider a coaxial system of two thin convex lenses of focal length f each separated by a distan... - YouTube
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