Q 12-10-014NEETJEE MainTop questionMedium
The intensities of two coherent sources are in the ratio $9 : 1$. The ratio of maximum to minimum intensity in their interference pattern is
Answer: (C) $4 : 1$
Concept. $\dfrac{I_{\max}}{I_{\min}} = \left(\dfrac{a_1 + a_2}{a_1 - a_2}\right)^2$ with $a \propto \sqrt I$.
Step 1. Amplitudes. $3 : 1$.
Step 2. Ratio. $\left(\dfrac{4}{2}\right)^2 = 4$.
Answer. $4 : 1$ (Option C).
Solution by Sreeraj P, M.Sc Physics