Let \\\\(\\omega\\\\) be the dispersive power of the material of the lens. Then, the chromatic aberration between violet and red colors is given by:\\\\(f_R-f_V=\\omega \ imes f_Y=(\\dfrac{n_V-n_R}{n_Y-1})f_Y=(\\dfrac{1.66-1.62}{1.64-1})\ imes 10=0.625cm\\\\)