If the two sources of light emit waves of different amplitudes and interfere then

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Let the amplitudes of the two interfering waves be $A_{1}$ and $A_{2}$ .

The intensity of light at any point in the interference pattern is given by $I = I_{1} + I_{2} + 2 I_{1} I_{2} cos ϕ$ , where $I_{1} \propto A_{1}^{2}$ and $I_{2} \propto A_{2}^{2}$ .

For destructive interference, the phase difference $ϕ = (2 n + 1) π$ , which gives $cos ϕ = - 1$ .

The minimum intensity is $I_{min} \propto (A_{1} - A_{2})^{2}$ .

Since the two sources emit waves of different amplitudes, $A_{1} \neq = A_{2}$ .

Therefore, $I_{min} \neq = 0$ . This means that there is some intensity of light in the region of destructive interference, and complete darkness is not achieved.

Answer: there is some intensity of light in the region of destructive interference.

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