Transients, RC circuits

Problem:

In the circuit shown, the switch is opened at t = 0, after having been closed for a long time.  Find the current I as a function of time for t > 0.

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Solution:

Problem:

Consider the RC circuit below with a switch S that can be opened and closed.

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The capacitor is uncharged when, at t = 0, the switch is closed.  Current begins to flow and the capacitor will charge. 
(a)  Write the equation relating the charge on the capacitor Q(t) and the current in the circuit I(t) to V0 and time. 
(b)  Solve for the voltages VC(t) across the capacitor and VR(t) across the resistor.
(c)  Sketch VC(t) and VR(t).

 Solution:

Problem:

(a)  Suppose a capacitor is charged by a voltage source, and then switched to a resistor for discharging.  Would a larger capacitance value result in a slower discharge, or a faster discharge?  How about a larger resistance value? 

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(b)  Now consider an inductor, "charged" by a current source and then switched to a resistor for discharging.  Would a larger inductance value result in a slower discharge, or a faster discharge?  How about a larger resistance value?

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Solution: