(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Determine the value of the current labeled i and the voltage labeled v at t=0+, t= 1.5 ms, and t = 3.0 ms.

2. Relevant equations

Ohm's law: v = i *r

Decay in source free RC Circuit v(t) = v@0 * e^(-t/RC)

3. The attempt at a solution

i(0-) = 0.1 A.

Therefore,

v across 200 ohm = 200* 0.1 = 20 V

Since no current flows through capacitor with constant dc current,

v across capacitor = 20 V @ t < 0

v across capacitor cannot change immediately as it would require infinite power so v across capacitor @ t = 0 = 20 V

Here's where the confusion is: Should I include the 200 ohm resistor in my RC circuit? Why or why not? Also, will my circuit be a source free RC circuit?

Also, what will be the current i through the 200 ohm resistor when t>0?

My last question is a theoretical one: Can a current through a resistor change immediately at one instant of time?

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# Homework Help: Circuit Analysis of driven RC Circuit with short circuits

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