Calculate the focal length of a convex lens of crown glass of dispersive power 0.012 and concave lens of dispersive power 0.020 that from an achromati

Monjur Alahi

Calculate the focal length of a convex lens of crown glass of dispersive power 0.012 and concave lens of dispersive power 0.020 that from an achromatic converging comination of focal length 0.3m when placed in contact.


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Salim Ahmed Kawsar

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Correct Answer - `r_("common")=1.11 m,0.644m`

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