A battery of emf is connected at to a network consisting of one resistor
PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Electric Circuits · Electric Circuits
Problem
A battery of emf 12V is connected at t=0 to a network consisting of one resistor R1=120Ω, a second resistor R2=220Ω, and two capacitors C1 and C2. Resistor R1 is in series with a branch that contains R2 in parallel with the capacitors, which themselves are connected in series with each other. The switch has been open for a long time so both capacitors are initially uncharged.
Answer the following questions qualitatively. No numerical calculations are required.
(a) Identify which single resistance value determines how quickly charge begins to flow onto the capacitors immediately after the switch is closed. Justify your answer in terms of the path that current follows at that instant.
(b) Suppose the two capacitors were instead connected in parallel with each other (still in parallel with R2). Describe how this change would affect the time required for the charge on either capacitor to reach approximately 63% of its final value. Explain your reasoning without performing explicit calculations.
(c) Now imagine that R1 is replaced by a resistor of twice the resistance while all other components remain unchanged. Explain qualitatively how the graph of capacitor charge versus time would be altered compared with the original circuit.