Question:
The radii of curvature for a thin convex lens are 10 cm and 15 cm respectively. The focal length of the lens is 12 cm. The refractive index of the lens material is
The radii of curvature for a thin convex lens are 10 cm and 15 cm respectively. The focal length of the lens is 12 cm. The refractive index of the lens material is
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Use the lensmaker's formula to relate the focal length, radii of curvature, and refractive index of the lens material.
Updated On: Apr 24, 2025
- 1.2
- 1.4
- 1.5
- 1.8
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The Correct Option is C
Solution and Explanation
\( \frac{1}{f} = (\mu - 1) \left( \frac{1}{R_1} - \frac{1}{R_2} \right) \)
\( \frac{1}{12} = (\mu - 1) \left( \frac{1}{10} - \frac{1}{-15} \right) \)
\( \frac{1}{12} = (\mu - 1) \left( \frac{3+2}{30} \right) \)
\( \mu = \frac{3}{2} \)
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