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hi guys this is the first time I come here so I'm sorry if it's against the rules or something, but could you confirm me if the answers are correct for each question?
this is an exam from last year and I wanted to see if my answers are correct since I don't trust whoever did it first.
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>>8455154
No source voltage?
What is V_f or V_t or V_+ or whatever that means
V_R2 = V_Z obviously
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>>8455178
Vf = source voltage
why is Vz = VR2? the zener is inteverted
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Of course it is inverted, that's the principle. It's in parallel to R2.
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>>8455232
so the answer to a) is wrong? Vr2 is not 2,21V but 4,73?
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fuck circuits
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>>8455235
sorry, my fault: V_R2=Vz only applies when the Z-diode is active which is not the case for a)
a) the source voltage is smaller than V_Z which means there's only one current path and V_f/(R1+R2)=V_R2/R2. Solve for V_R2. Note the factor R2/(R1+R2) for b)
b) without the Z-diode the voltage across R2 would be higher than V_Z, so current branches and V_R2=V_Z.
c) situation like b), If=V_R1/R1=(Vf-Vz)/R1
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