Answer the following T/F questions based on the behavior of the circuit in the above Figure 5:(1) A transient current flows for a short time after the RELAY is switched to either the N.O.("normally open") or N.C. ("normally closed") position.(2)The transient currents that flow in this experiment decays exponentially to zero.(3)The capacitor charge Q exponentially decays to zero when the RELAY is thrown to position N.O.(4)When the current I is positive, the capacitor charge Q is decreasing.(5)When the current I is positive, the measured VOLTAGE IN 2 will be negative.(6)When the capacitor charge Q is positive, the measured VOLTAGE IN 1 is positive.(7)The quantity t1/2=? ln 2 is called the half-life of an exponential decay, where ?=RC is the time constant in an RC circuit. The current in a discharging RC circuit drops by half whenever t increases by&nbsp;t12. For a circuit with R=2 k? and C=3 ?F, if the current is 6 am at t=5 ms, at what time (in ms) will the current be 3 mA?

Question

Answer the following T/F questions based on the behavior of the circuit in the above Figure 5:(1) A transient current flows for a short time after the RELAY is switched to either the N.O.(&quot;normally open&quot;) or N.C. (&quot;normally closed&quot;) position.(2)The transient currents that flow in this experiment decays exponentially to zero.(3)The capacitor charge Q exponentially decays to zero when the RELAY is thrown to position N.O.(4)When the current I is positive, the capacitor charge Q is decreasing.(5)When the current I is positive, the measured VOLTAGE IN 2 will be negative.(6)When the capacitor charge Q is positive, the measured VOLTAGE IN 1 is positive.(7)The quantity t1/2=? ln 2 is called the half-life of an exponential decay, where ?=RC is the time constant in an RC circuit. The current in a discharging RC circuit drops by half whenever t increases by&amp;nbsp;t12. For a circuit with R=2 k? and C=3 ?F, if the current is 6 am at t=5 ms, at what time (in ms) will the current be 3 mA?

au4gsf · Accepted Answer

1) True. The capacitor is initially uncharged, voltage on a capacitor cannot change instantaneously, therefore voltage before switch throw = voltage after and initial current is Vs/R.  2) True. At any point in time, the instantaneous current is (Vs-Vc)/R so as capacitor voltage increases, the current decreases until Vc=Vs and then I=0.  3) False. The charge increases exponentially until it reaches a steady state value when Vc=Vs. Then charge,q=CVs  4) False. With direction/polarity shown in the diagram,a positive I results in increasing charge on the capacitor.  5) False. The capacitor voltage will be positive and the voltage across the resistor will be positive at the &quot;top&quot; of the resistor, therefore IN 2 is positive.  6) False. VOLTAGE OUT 1 and VOLTAGE IN 1 are equal and always ZERO volts  7) The equation for the current is I(t)=(Vs/R)[1-exp(-t/RC)].You are given R and C, so use the data,I=6 ma at t=5 ms to determine that Vs/R = 10.6119 ma. Then solve for time when I=3 ma --&amp;gt; result is t=1.993 ms.

Answer the following T/F questions based on the behavior of the circuit in the above Figure 5:(1)

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