This is for Electronic Circuits One Lab With Inductors Capac

This is for Electronic Circuits One Lab With Inductors Capacitors and Such

How do you explain that ll and 12 in time = are equals but with a different sign meanwhile 10 goto 0. V_a(0) = -20V, V_C(0) = -30V, V_d(0) = 2S0V The circuit above shows a four capacitors that are connected across the current source Is. Identify which capacitors are in series and which are in parallel? Which inductor(s) are in series? What is the value of Vb[0)? What is the equivalent capacitance seen by the source?

Solution

6 ans)

Given Is=-5exp(-50t) mA

time t=oo(infinity) Is=0,so as Io=-Is=0; given the direction of I0 or Ib is opposite to \'Is \' so Io=0 A

and as Is=0 the circuit is like open circuit with capacitors charged to some voltage

then there is a closed path for current flow for capacitors in parallel(i.e 200 and 800 uF) so

current circulates between these two capacitors such that I₁=-I₂

7 ans)

a) there is no inductors in the circuit

200uF and 800uF capacitors are in parallel and

5uF and 1.25 uF in series

b) Vb(0)=-(Va(0)+Vc(0)+Vd(0))=-(-20-30+250)=-(200)=-200 V

Vb(0)=-200 V

c)Equivalent capacitance

200uF and 800 uF parallel gives 200+800=1000uF

Now 1000uF,5uF and 1.25uF are in series

Ceq=(1/(1/1000+1/5+1/1.25))uF=0.999uF ~1uF

Equivalent capacitance Ceq=1uF