Assertion: Critical angle is minimum for viol | vedclass

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(A) The critical angle $	heta_c$ is given by the formula $	heta_c = \sin^{-1} \left( \frac{1}{\mu} ight)$.According to Cauchy's dispersion formula

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If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

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(A) The critical angle $	heta_c$ is given by the formula $	heta_c = \sin^{-1} \left( \frac{1}{\mu} ight)$.According to Cauchy's dispersion formula,the refractive index $\mu$ of a medium is inversely proportional to the square of the wavelength $\lambda$ (approximately $\mu \propto \frac{1}{\lambda}$ for visible light).Since the wavelength of violet light is the minimum among visible colors,the refractive index $\mu$ for violet light is the maximum.As $	heta_c = \sin^{-1} \left( \frac{1}{\mu} ight)$,a higher value of $\mu$ results in a smaller value of $	heta_c$.Therefore,the critical angle is minimum for violet color. Both the Assertion and the Reason are correct,and the Reason correctly explains the Assertion.

Assertion: Critical angle is minimum for violet colour.
Reason: Because critical angle $\theta_c = \sin^{-1} \left( \frac{1}{\mu} \right)$ and $\mu \propto \frac{1}{\lambda}$.

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Assertion: Critical angle is minimum for violet colour.Reason: Because critical angle $\theta_c = \sin^{-1} \left( \frac{1}{\mu} \right)$ and $\mu \propto \frac{1}{\lambda}$.