When light rays from the sun fall on a convex | vedclass

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(B) The focal length $f$ of a lens is given by the Lens Maker's Formula: $\frac{1}{f} = (n - 1) \left( \frac{1}{R_1} - \frac{1}{R_2} \right)$.Since th

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Focal length for violet colour is the shortest.

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(B) The focal length $f$ of a lens is given by the Lens Maker's Formula: $\frac{1}{f} = (n - 1) \left( \frac{1}{R_1} - \frac{1}{R_2} \right)$.Since the refractive index $n$ of a material depends on the wavelength $\lambda$ of light,the focal length also depends on the wavelength.According to Cauchy's relation,the refractive index $n$ is higher for shorter wavelengths (violet) and lower for longer wavelengths (red).Since $n_v > n_r$,the term $(n - 1)$ is larger for violet light than for red light.Consequently,the focal length $f$ is inversely proportional to $(n - 1)$,meaning $f_v Therefore,the focal length for violet light is the shortest.

When light rays from the sun fall on a convex lens along a direction parallel to its axis,which of the following statements is true?

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