Determining Current Direction in a Charging RC Circuit

AI Thread Summary
In a charging RC circuit, when the switch is closed, current flows clockwise from the battery through resistor R1. The confusion arises regarding the direction of current from the capacitor, which flows counterclockwise through the switch to resistor R2. Once the capacitor is fully charged, the battery is effectively disconnected, and the capacitor then discharges through R2. Understanding the flow direction involves recognizing the roles of the battery and capacitor during the charging and discharging phases. Clarifying these concepts is essential for accurate analysis of the circuit behavior.
jolly_math
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Homework Statement
In the diagram below, the switch S has been open for a long time. It is then suddenly closed. TakeEe = 10.0 V, R1 = 50.0 kΩ, R2 = 100 kΩ, and C = 10.0 µF. Let the switch be closed at t = 5.0 s. Determine the current in the switch as a function of time.
Relevant Equations
I(t) = -I/RC * e^(-t/RC)
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After the switch is closed, current flows clockwise from the battery to resistor R1 and down through the switch.

I don't understand the reasoning for the following: the current from the capacitor flows counterclockwise and down through the switch to resistor R2. How do I determine the direction of current when a capacitor is charging? Thank you.
 
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jolly_math said:
I don't understand the reasoning for the following: the current from the capacitor flows counterclockwise and down through the switch to resistor R2. How do I determine the direction of current when a capacitor is charging? Thank you.
This capacitor is fully charged when the switch is closed. At that point the battery is effectively disconnected from the capacitor and the capacitor discharges through ##R_2##. Are you asking about a different problem?
 
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