d
\(A\,\, = \,\,\frac{\pi }{3}\,\, = \,\,{60^ \circ };\,\,\,{\delta _m} = \,\,\frac{\pi }{6}\,\, = \,\,{30^ \circ };\,\,\,c\,\, = \,\,3\,\,\, \times \,\,{10^8}\,\,m{s^{ - 1}};\,\,\,\,v\,\, = \,\,?\)

\(\,\,\mu \,\, = \,\,\,\frac{{sin\frac{{A + {\delta _m}}}{2}}}{{\sin \frac{A}{2}}}\,\, = \,\,\,\frac{c}{v}\) અથવા \(\,\,v\,\, = \,\,c\,\,\frac{{sin\frac{A}{2}}}{{\sin \,\,\frac{{A + {\delta _m}}}{2}}}\,\, = \,\,\,\frac{{3\,\, \times \,\,{{10}^8} \times \,\,\sin \,\frac{{{{60}^ \circ }}}{2}}}{{\sin \,\frac{{{{60}^ \circ } + {{30}^ \circ }}}{2}}}\)

\( = \,\,\frac{{3\,\, \times \,\,{{10}^8} \times \,\,\sin {{30}^ \circ }}}{{\sin {{45}^ \circ }}}\,\, = \,\,\,\,\frac{{3\,\, \times \,\,{{10}^8} \times \,\,0.5}}{{0.7071}}\,\, = \,\,\,2.12\,\, \times \,\,{10^8}\,\,m{s^{ - 1}}\)