Dear members of All About Circuits, I'm asking for some help because I am a little bit confused about circuit analysis.
In the attachment there is the circuit I need to analyse, and I need to find the Voltage V across the 12Ω resistor.
I was trying to analyse it by using superposition. My idea was to get the total current through the circuit and then, multiplying it by 12Ω, I was looking for the voltage across 12Ω resistor. (Possibly I am already wrong).
Steps I've done:
1) Leave the 50V source, then [(20+12) || 40] + 10 = 27.7Ω. Then 50/27.7=1.8A
2) Leave the 40V source. (40||10)+12+20 = 40. Then -40/40=-1
3) Leave the 8A source. Here comes the problem. Doing (10||40+12)=20. Then I have a 8A source in parallel with 2 resistors of 20Ω each. What I thought is: current divider=4A per side.
The actual problem is: if I sum all these current I get 4.8A, which multiplied by 12=57.6V.
With a circuit simulator I get that the voltage drop is 48 (120V on the right side and 72 on the left). And 48/12=4, like the value I got from step 3.
My silly idea is: shall I consider every single loop, and since the 12Ω resistor is "in the loop" with 4A, easily multiply that current times the resistance to find the voltage across that resistor?
I'm sorry for this confusing message, I hope that someone can help me.
Thanks in advance.
All the best
In the attachment there is the circuit I need to analyse, and I need to find the Voltage V across the 12Ω resistor.
I was trying to analyse it by using superposition. My idea was to get the total current through the circuit and then, multiplying it by 12Ω, I was looking for the voltage across 12Ω resistor. (Possibly I am already wrong).
Steps I've done:
1) Leave the 50V source, then [(20+12) || 40] + 10 = 27.7Ω. Then 50/27.7=1.8A
2) Leave the 40V source. (40||10)+12+20 = 40. Then -40/40=-1
3) Leave the 8A source. Here comes the problem. Doing (10||40+12)=20. Then I have a 8A source in parallel with 2 resistors of 20Ω each. What I thought is: current divider=4A per side.
The actual problem is: if I sum all these current I get 4.8A, which multiplied by 12=57.6V.
With a circuit simulator I get that the voltage drop is 48 (120V on the right side and 72 on the left). And 48/12=4, like the value I got from step 3.
My silly idea is: shall I consider every single loop, and since the 12Ω resistor is "in the loop" with 4A, easily multiply that current times the resistance to find the voltage across that resistor?
I'm sorry for this confusing message, I hope that someone can help me.
Thanks in advance.
All the best
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