n = \(\frac{\frac{A+D}{2}}{sin\frac{A}{2}}\) where A = the refracting angle of the prism(60º) D = angle of deviation of the ray (30^\circ) n = \(\frac{\frac{60+30}{2}}{sin\frac{60}{2}}\) = \(\frac{sin45}{sin30}\) v = \(\frac{\frac{1}{\sqrt{2}}}{\frac{1}{2}}\) \(\frac{\frac{\sqrt{2}}{2}}{\frac{1}{2}}\) = \(\frac{\sqrt{2}}{2}\) x \(\frac{2}{1}\) = \(\sqrt{2}\) n = \(\sqrt{2}\)