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F≈(E_dc+E_ac )^2-(E_dc+E_ac )^2=4E_dc E_ac
Where
E_dc = electret exhibited D.C potential
E_ac = applied signal voltage
Electret microphone is used in close range. Electret microphone quality can be made better by improving material and size. Electret microphone is used in mobile devices and which make it
Source of charasteristics:
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