No links please If a lens of flint glass of dispersive powers 0.066 be combined with another of crown glass of dispersive power 0.033 and focal length 0.60m to form an achromatic doublet,then what will be the focal length of flint glass lens? Share with your friends Share 2 Vijay Shankar Yadav answered this Dear Student, We have dispersive power for lens=-dffso net dispersive power =-dfcfclet focal length of lenses are f1 and f2so -dfcfc=-d1f1+1f21f1+1f2=-w1f1-w2f21f1+1f2=0hence w1f2=-w2f1hence according to question .066×.6=-.033×f1f1=-1.2m Regards 6 View Full Answer