11. The circuit in the figure has a capacitor, C = 4.60 mF, connected to a V-60-

Question

11. The circuit in the figure has a capacitor, C = 4.60 mF, connected to a V-60-V battery, two switches, and three resistors (R1-340 , R2-220 , and R3-130 . Initially, the capacitor is uncharged and both of the switches are open. a) Switch S, is closed. What is the current flowing out of the battery immediately after switch S, is closed? After 10.0 min, switch S2 is closed. What is the current flowing out of the battery immediately after switch S2 has been closed? b) c) What is the current flowing out of the battery 10.0 min after switch S has been closed? d) Afte r another 10.0 min, switch S, is opened. How long will it take until the current in the resistor R2 is 1.00 mA? R. R2

Explanation / Answer

a)

total resistance of the circuit , R= R1 + R3 = 340 + 130 = 470 ohm

V = Voltage = 6 volts

current coming from battery = i = V/R = 6 / 470 = 0.0128 A

b)

in loop CDEFC , using KVL

q/C + i' R2 - (i - i') R3 = 0

0/ C + i' R2 - (i - i') R3 = 0                       immediately after s2 closed , q = 0

220 i' - 130 (i - i') = 0

350 i' = 130 i    

i = 2.7 i'             eq-1

Using KVL in loop ABCFA

(i - i') R3 + i R1 = V

130 (2.7 i' - i') + 340 (2.7i') = 6                         eq-2

i' = 0.0053 A

i = 0.0143 A

c)

Voltage across R3 = (i - i') R3 = 1.17 volts

in loop CDEFC , using KVL

q/C + i' R2 - 1.17 = 0

i'' t/ C + i'' R2 - 1.17= 0

t = 600 sec ,

(600 i'' / 0.0046) + 220 i'' = 1.17

i'' = 8.95 x 10-6

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.