Physics - Wave Optics Question with Solution | TestHub

When path difference is zero, the resultant intensity $I=4I_0$, where $I_0$ is the intensity of the individual waves. When the path difference is $\frac{\lambda }{2}$, the intensity $I^{\prime }=0$ $\therefore \frac{I}{I^{\prime }}=\frac{4I_0}{0}=\infty$