Question

The Cauchy's dispersion formula is

• A. $n=A+B\lambda^{-2}+C\lambda^{-4}$
• B. $n=A+B\lambda^{-2}+C\lambda^{4}$
• C. $n=A+B\lambda^{2}+C\lambda^{-4}$
• D. $n=A+B\lambda^{2}+C\lambda^{4}$

Answer 1

Answer: (A)

The Cauchy’s dispersion formula represents the dispersion of most of the substances with considerable accuracy. Also from the Cauchy’s dispersion formula if $n$ is refractive index and $A, B$ and $C$ are constants, then $n = A + B \lambda^{-2} + C\lambda^{-4}$.