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Cisneros778
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Homework Statement
The circuit in the figure has a capacitor connected to a battery, two switches, and three resistors. Initially, the capacitor is uncharged and both of the switches are open.
(a) Switch S1 is closed. What is the current flowing out of the battery immediately after switch S1 is closed?
.015 A
(b) After about 10 min, switch S2 is closed. What is the current flowing out of the battery immediately after switch S2 is closed?
.0164 A
(c) What is the current flowing out of the battery about 10 min after switch S2 has been closed?
(d) After another 10 min, switch S1 is opened. How long will it take until the current in the 200-Ω resistor is below 1 mA?
Homework Equations
I(t) = V/R * e^(-t/(RC))
The Attempt at a Solution
I am stuck on (c) right now.
At first I just used the equation above and plugged in the total Resistance and 600s for time. The answer I got was obviously wrong because the problem is asking for the current coming OUT OF the battery. The current will split two ways, one going to the 100 ohm resistor and the other towards the capacitor and the 200 ohm resistor.
I then figure to only use the equation to solve for the current going to the capacitor and then use the ratio to find the current coming out of the battery. This does not work because the value for current that I get is so close to zero that the current coming out of the battery might as well be zero.
Does the resistor, R, in the equation mean the total resistance of the circuit or just the 200 ohm resistor in series with the capacitor?