(a)
Draw the equivalent circuit with one resistor and one capacitor.
(a)
Answer to Problem 88P
The equivalent circuit has been drawn.
Explanation of Solution
The resistor
The capacitors
This capacitor is in series with
Substitute the value of
Conclusion:
Substitute
Substitute
The equivalent circuit with the equivalent resistance and capacitance values is shown below.
fig
(b)
Find the charge on the capacitor
(b)
Answer to Problem 88P
The charge on the capacitor is
Explanation of Solution
The current in resistor with fully charged capacitor is zero as there is no flow of charge from the battery to the capacitor.
Write the equation for charge on equivalent capacitor
Here
Conclusion:
Substitute
This charge is same across
Then the voltage drop across the capacitors
Then the charge on the capacitor
The charge on the capacitor is
(c)
Time constant of the circuit.
.
(c)
Answer to Problem 88P
Time constant of the circuit is
Explanation of Solution
Write the equation for time constant
Here
Conclusion:
Substitute
Time constant of the circuit is
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Chapter 18 Solutions
Physics
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