Question

If R₁ and R2 are the radii of curvature, n is the refractive index and f is the focal length, then the lens maker's formula is given by

• A. \(f=(n-1)(\frac{1}{R_1}-\frac{1}{R_2})\)
• B. \(f=(n-2)(\frac{1}{R_1}-\frac{1}{R_2})\)
• C. \(\frac{1}{f}=(n-2)(\frac{1}{R_1}-\frac{1}{R_2})\)
• D. \(\frac{1}{f}=(n-1)(\frac{1}{R_1}-\frac{1}{R_2})\)

Answer 1

The Correct Option is D

The lens maker's formula relates the focal length \( f \) of a lens to the radii of curvature \( R_1 \) and \( R_2 \), the refractive index \( n \), and the focal length \( f \). The formula is given by: \[ \frac{1}{f} = (n - 1) \left( \frac{1}{R_1} - \frac{1}{R_2} \right) \] This is the correct form of the lens maker's equation.

The correct option is (D): \(\frac{1}{f}=(n-1)(\frac{1}{R_1}-\frac{1}{R_2})\)