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Question
Is it necessary to have two waves of equal intensity to study interference pattern? Will there be an effect on clarity if the waves have unequal intensity?
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Solution
Interference pattern can be studied with waves of unequal intensity.
\[I =I_1 + I_2 + 2\sqrt{\left[ I_1 \times I_2 \right]}\cos\left( \phi \right),\]
where
\[\phi =\text{ phase difference}\]
In case of waves of unequal intensities, the contrast will not be clear, as the minima will not be completely dark.
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