A capacitor used to provide steady voltages in the power supply of a stereo amplifier charges rapidly to 35 V every 1/60 second. It must then hold that voltage to within 1.0 V for the next 1/60 s while it discharges through the amplifier circuit. If the circuit draws 1.2 A from the 35-V supply, what is its effective resistance (in ohms)? What value of capacitance is needed (in mF)?
The discharging voltage for a capacitor is:
where
This means that when the capacitor is discharging:
solving for tau:
while the capacitor is charging:
If:
A capacitor used to provide steady voltages in the power supply of a stereo amplifier charges...
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