f_V and f_R are the focal lengths of a convex | vedclass

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(B) The refractive index of a material is higher for violet light than for red light $(n_V > n_R)$.For a convex lens,the focal length is given by the

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$f_V  F_R$

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(B) The refractive index of a material is higher for violet light than for red light $(n_V > n_R)$.For a convex lens,the focal length is given by the lens maker's formula: $\frac{1}{f} = (n - 1) \left( \frac{1}{R_1} - \frac{1}{R_2} \right)$. Since $n_V > n_R$,the power of the lens is greater for violet light,meaning the focal length $f_V$ is smaller than $f_R$ $(f_V For a concave lens,the focal length is negative. The magnitude of the focal length $|F|$ follows the same logic as the convex lens,where $|F_V|  F_R$ (e.g.,$-2 > -5$).

$f_V$ and $f_R$ are the focal lengths of a convex lens for violet and red light respectively,and $F_V$ and $F_R$ are the focal lengths of a concave lens for violet and red light respectively. Then:

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