Question

Use the same circuit diagram: completely uncharged, In that circuit, emf = 1.2 KV, C = 6.5 pF, R = R = R' = 0.73 MO2. With switch S is closed (at t = 0). At t = 0, what are a. Currenti, in resistor ? b. Current iz in resistor ra? c. Current in resistors? Att (that is after many time constants), d. What are is?, e 67 1 ? What is the potential difference V, across Rat E. h i. T T-O and op? Sketch V, versust between these two extreme limits.

Please dont answer if your not going to explain, I will need to repost and waste a question.

Answer 1

I t-o R₂Z & R3 =c1 Given, E = 1.2 kV C = 6.5 ur R, = R2 = Rz = 0.73M. 'C' is completly uncharged before t = 0. 1 ie V6 (0-) = 0 The capacitor does not allow sudden change of voltage across it. so yc (0+) = vc 10-) = 0 volt That means as soon as switch is closed at t = 0, the capacito behaves as short circuit. So circuit at t=0 is shown below - R₂ § {R3 (a) Current is in R2: - pero where Req = R + R21 R₂ = RIT R2 R3 R2+R3 = 1.095 ML 7 i = 1200 ,- 1.09 MA 1.095 X106 → li = 1.09mA]

(6) Current in resistor Rz i.e. iz. As R2 = R3 so current 12 = 18 lze > iz = 1 = 0.545mA R2 + R₃ 12 = 0.545 mA (C) Cworent in resistor Rg le iz But R₂ = Rz. → iz = 1 = 0.545mA →liz - 0.545 mA) As t o the capacitor acts as open circuit. So circuit at t - is given below. E = d.) calculating in Νοω ι - ε . Ri+R2 1200 0.73 M2 +0.73M.R >Ti = 0.821MA iz = i;= 0.82 IMA (fi) As Capacitor is open circuit so no cuorent flows through R3 = 3 = 0 À

(g) at T=0, using circuit drawn at t = o. Vz = iz Rg' = 0.545 x 10-ºx 0.73x106 [ V3 = 397.85 volts] (h) at Teco, using circuit drawn at t = co vz = iz Rz = 0 x 0.73x106 → V3 = 0 volts (i) V decreases exponentially as T varies between o to o. +397.85