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satellitelove
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Homework Statement
A parallel plate capacitor having two square plates each of side length 10mm has a plate separation of 100μm.
It is used to make a microphone where the sound waves cause the plate separation to change by +/- 10μm.
The microphone capacitor is connected in series with a constant 1 volt d.c. source of zero internal impedance and an amplifier with an input that can be regarded as a 10pF capacitor, the three components forming a complete circuit.
What is the peak to peak input voltage of the amplifier caused by the plate movement of +/-10μm ?
Assume the capacitor microphone has its gap filled with air.
Homework Equations
ε = 8.854 x 10^-12
The Attempt at a Solution
Having a bit of trouble. I'm not sure where exactly to start.
Q = CV
where C = epsilon x A/d
A change in plate separation cause a change in charge across the plates. But I'm looking for a change in voltage. Any ideas are appreciated.
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