Question

In YDSE, if sources are incoherent, the intensity on screen is $13 I_{0}$. When these sources are coherent then minimum intensity on screen is $I_{0}$. If maximum intensity produced by these coherent sources on screen is $n^{2} I_{0}$, then find $n$.

Answer 1

$\dot{I}_{1}+I_{2}=13 I_{0}$
$\left(\sqrt{I_{1}}-\sqrt{I_{2}}\right)^{2}=I_{0}$
$I_{1}+I_{2}-2 \sqrt{I_{1}} \sqrt{I_{2}}=I_{0}$
$2 \sqrt{I_{1}} \sqrt{I_{2}}=12 I_{0}$
$I_{\max }=13 I_{0}+12 I_{0}=25 I_{0}=(5)^{2} I_{0}$