The power of a biconvex lens is 10 D and the radius of curvature of each surface is 10 cm. Then the refractive index of the material of the lens is:
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The power of a biconvex lens is 10 D and the radius of curvature of each surface is 10 cm. Then the refractive index of the material of the lens is:

G1 Physics · Accepted Answer

Step 1: F = 1/P = 0.10 m. Step 2: Lens-maker formula: 1/f = (μ − 1)(1/R₁ − 1/R₂). Step 3: For two equal convex faces R₁ = +0.10 m and R₂ = −0.10 m: 10 = (μ − 1)(10 + 10). Step 4: μ − 1 = 1/2, so μ = 3/2. Final answer: (D) 3/2.