\[ \theta {\text{ = (}}{{\text{n}}_{\text{v}}} - {{\text{n}}_{\text{R}}})A\]
Where :
\[ {\delta _{\text{y}}}{\text{ = (}}{{\text{n}}_y} - 1)A\]
Where :
\[ \omega = \frac{{{\text{(}}{{\text{n}}_{\text{v}}} - {{\text{n}}_{\text{R}}})}}{{{\text{(}}{{\text{n}}_y} - 1)}}\]
Where :