z_{e} = 6, 33 \cdot \frac{10^{- 7}}{2 π \sqrt{(\frac{\sin 50^{\circ}}{\frac{1}{1, 6}})^{2} - 1}} = 8, 2 \cdot 10^{- 8} m

${z_e=6,33\cdot \frac{10^{-7}}{2 \pi \sqrt{ \bigg(\frac{\sin 50^\circ }{\frac{1}{1,6} }\bigg)^2-1}} =8,2 \cdot 10^{-8}\, \mathrm{m}}$

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