I'm trying to work out the Itotal in the circuit.
I have used nodal analysis;
though unsure if this is right:
V1-25 + V1/10 + V1-V2/20 = 0
(1/10+1/20)V1 + (1/20)V2 = 1-25
0.15V1 + 0.05V2 = -24 ............. (1)
&
V2-V1/20 + V2+50/30 + V2/60 = 0
(1/20)V1 + (1/20+1/30+1/60)V2 = 50/30
0.05V1 + 0.1V2 = 1.66666 ..........(2)
I get V1 = -198.6666
V2 = 116
yet this can't be right... please help....
I used Ohms law and figured out that 25V is over R1, Ir1 = 2.5A.
I used a circuit simulation to find Itotal, which = 3.958A (yet I don't seem to be able to use Ohms Law to find Itotal. I have calculated the total 'R' in the circuit to be 8ohms (also verified by the circuit simulation); yet 75 (Vtotal) / 8 Rtotal = 9.375A (this can't be correct, the circuit simulation tells me it's definately 3.958A).
PLEASE HELP ME
Also; by using 3.958A as the cct total, I minused 2.5A=Ir1 to find Ir2, therefore Ir2 * R2 = 29.16V over R2. so I would assume at node 2 there would be a voltage of 29.16V, yet, the simulation tells me it's -4.16V.....
So NOW I'M COMPLETLY CONFUSED
Please help ((
I need to know how to calculate out Itotal, and at Node 2, how to work out voltage drops and associated I's.
Thanks in advance.
I have used nodal analysis;
though unsure if this is right:
V1-25 + V1/10 + V1-V2/20 = 0
(1/10+1/20)V1 + (1/20)V2 = 1-25
0.15V1 + 0.05V2 = -24 ............. (1)
&
V2-V1/20 + V2+50/30 + V2/60 = 0
(1/20)V1 + (1/20+1/30+1/60)V2 = 50/30
0.05V1 + 0.1V2 = 1.66666 ..........(2)
I get V1 = -198.6666
V2 = 116
yet this can't be right... please help....
I used Ohms law and figured out that 25V is over R1, Ir1 = 2.5A.
I used a circuit simulation to find Itotal, which = 3.958A (yet I don't seem to be able to use Ohms Law to find Itotal. I have calculated the total 'R' in the circuit to be 8ohms (also verified by the circuit simulation); yet 75 (Vtotal) / 8 Rtotal = 9.375A (this can't be correct, the circuit simulation tells me it's definately 3.958A).
PLEASE HELP ME
Also; by using 3.958A as the cct total, I minused 2.5A=Ir1 to find Ir2, therefore Ir2 * R2 = 29.16V over R2. so I would assume at node 2 there would be a voltage of 29.16V, yet, the simulation tells me it's -4.16V.....
So NOW I'M COMPLETLY CONFUSED
Please help ((
I need to know how to calculate out Itotal, and at Node 2, how to work out voltage drops and associated I's.
Thanks in advance.
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