Hello,
this information was provided by our Professor:
U1(t) had for long time an initial value of 12 V.
At t = 0.5 ms the U1(t) drops to 0 V. (You can see that in the graph at the bottom of the page).
Parts A and B I solved by myself and I got the same results as my Prof.
A) U2(t) @ 0 ms? Result: 3 V. Method: Simple Voltage divider.
B) What is the Voltage across the capacitor @ 0 ms? Result 9 V. I just subtracted 12 V  3 V = 9 V. Is that all I have to do?
I am struggling with part C.
I get the same equivalent circuit and it appears to me, that he uses the Voltage divider formula ( 12 V * R1/(R1+R(TH)) ), but I am not certain (at all) why he does that? The next step is equally puzzling, why is he subtracting 1 V  9 V?
Is there a different equivilant circuit that I could use?
Tobias
this information was provided by our Professor:
U1(t) had for long time an initial value of 12 V.
At t = 0.5 ms the U1(t) drops to 0 V. (You can see that in the graph at the bottom of the page).
Parts A and B I solved by myself and I got the same results as my Prof.
A) U2(t) @ 0 ms? Result: 3 V. Method: Simple Voltage divider.
B) What is the Voltage across the capacitor @ 0 ms? Result 9 V. I just subtracted 12 V  3 V = 9 V. Is that all I have to do?
I am struggling with part C.
I get the same equivalent circuit and it appears to me, that he uses the Voltage divider formula ( 12 V * R1/(R1+R(TH)) ), but I am not certain (at all) why he does that? The next step is equally puzzling, why is he subtracting 1 V  9 V?
Is there a different equivilant circuit that I could use?
Tobias
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