f1=(μ−1)[R11−R21]251=0.5[R1−(2R1)]251=100.5[R3]R=475=18.75R1=18.75 cm,R2=37.5 cm
A double convex lens has focal length 25 cm. The radius of curvature of one of the surfaces is doubled of the other. Find the radii, if the refractive index of the material of the lens is 1.5.
Held on 30 Apr 2019 · Verified 9 Jul 2026.
100 cm,50 cm
25 cm,50 cm
18.75 cm,37.5 cm
50 cm,100 cm
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