An object is located 36 cm to the left of a biconvex lens of index of regraction 1.5. The left surface of the lens has a radius of curvature of 20 cm. The right surface of the lens is to be shaped so that a real image will be formed 72 cm to the right of the lens. What is the required radius of curvature for the second surface?(adsbygoogle = window.adsbygoogle || []).push({});

I asked earlier on this, but I still got it wrong: this is what I did -

I used 1/F=(n-1)(1/R1 + 1/R2)

1/72 = (1.5 - 1) (1/.2 + 1/R2)

Solved it and got R2 to equal 45 cm. I am pretty sure 1/F shouldnt be 72, but if its unknown that would make it unsolvable unless I am missing something?

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# Homework Help: Biconvex Lens

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