Olá,
ismaelmat
Pela Lei de Snell, temos
[tex3]\mathsf{n_1 \cdot\sen \theta_1 = n_2 \cdot \sen \theta_2}[/tex3]
Sendo [tex3]\mathsf{n_1 = 1, \,\, n_2 = n_x, \,\, \sen \theta_1 = \frac{1}{2}, \,\, \sen \theta_2 = \frac{\sqrt{3}}{2}}, [/tex3]
vem
[tex3]\mathsf{1 \cdot \frac{1}{2} = n_x \cdot \frac{\sqrt{3}}{2}} \,\,\,\, \Rightarrow \,\,\,\, \boxed{\mathsf{n_x = \frac{\sqrt{3}}{3}}}[/tex3]