A bicovex lens has radii of cuvature 20 cm each. If the refractive index of the material of the lens is 1.5, what is its focal length?

Explanation

To find the focal length of a biconvex lens with given radii of curvature and refractive index, we can use the lens maker's formula. Let's go through the solution step by step.

### Step 1: Identify the Given Values
- The radius of curvature for the first surface (R1) = +20 cm (convex surface)
- The radius of curvature for the second surface (R2) = -20 cm (convex surface, but considered negative in the lens maker's formula)
- The refractive index (μ) = 1.5

### Step 2: Write the Lens Maker's Formula
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