can anyone help me or explain me how to get the voltage in my circuits ,, i get the RL =8 ohms and 3.24324V ,, and my RTH is =60/11 ... now i put the voltage on the circuits and i dont know to get all the voltage .>> help me guys thanks
helpppYour post is incomprehensible.
1 State and show the problem as presented to you. Uniquely identify each element in the circuit.
2. Then show, step by step, how you arrived at a solution - as far as you got anyway.
yes .. all across voltage . they are not asking to replace the RL but the voltage across all resistor ... i dont know how to find those voltages when i get the RL voltage helpI'm puzzled by the statement of the problem. Is it your understanding that you are to find Vth and Rth, and then use that result to find the voltages across all the other resistors in the circuit? Are they asking for those other voltages when RL is in place, or not?
thank you ,,, but i dont understand why is that i will get RL voltage if i can use loop or nodal analysis. if for example i replace RL with another resistor value ? and get the voltage of it. after that i will use nodal and lopp analysis to get all the voltages??? thanks helpHi,
Do you know Nodal Analysis or Loop Analysis or anything else like that?
You could use Nodal to get all the voltages for example.
You write one equation for each node, then solve them simultaneously.
thank you ,,, but i dont understand why is that i will get RL voltage if i can use loop or nodal analysis. if for example i replace RL with another resistor value ? and get the voltage of it. after that i will use nodal and lopp analysis to get all the voltages??? thanks help
thank you so much ..Hi,
You can start with Nodal, you dont have to do that later.
But you need to label everything as in the attachment shown below.
See if that helps.
When you solve, you'll get all the voltages shown, then you can subtract to get the voltages across each resistor.
For example, the equation at v2 could be:
(v1-v2)/R1+(v4-v2)/R3=(v2-v3)/R2
and that is just the sum of currents entering the node at v2 equated to the sum of currents leaving the node at v2.
You can also do it as the sum of all currents entering the node.
Also note that voltages v1, v3, and v5 are already known because of the placement of the ground (GND) which is taken to be at zero volts and all the sources are connected in series. This means only three voltages are unknown so you only need three equations, for v2, v4, and v6.
Can it only solve by nodal ? or any theorem can solve it? am not familiar in nodal theorem . help thanks very muschHi,
You can start with Nodal, you dont have to do that later.
But you need to label everything as in the attachment shown below.
See if that helps.
When you solve, you'll get all the voltages shown, then you can subtract to get the voltages across each resistor.
For example, the equation at v2 could be:
(v1-v2)/R1+(v4-v2)/R3=(v2-v3)/R2
and that is just the sum of currents entering the node at v2 equated to the sum of currents leaving the node at v2.
You can also do it as the sum of all currents entering the node.
Also note that voltages v1, v3, and v5 are already known because of the placement of the ground (GND) which is taken to be at zero volts and all the sources are connected in series. This means only three voltages are unknown so you only need three equations, for v2, v4, and v6.
You say that your RTH is 60/11. I have to assume that that is a resistance and therefore 60/11 Ω. In your image, however, you are adding that 60/11 to a voltage. So is it a voltage or is it a resistance? If it's a resistance, then how can you add it to a voltage. TRACK YOUR UNITS!!!can anyone help me or explain me how to get the voltage in my circuits ,, i get the RL =8 ohms and 3.24324V ,, and my RTH is =60/11 ... now i put the voltage on the circuits and i dont know to get all the voltage .>> help me guys thanks
Using the TS's image, here's how I get Rth:I did not get the same Thevinin values that you got so I think you did it wrong and your notation is impossible to follow so I don't have any idea what you did wrong.
I got the same Rth.Using the TS's image, here's how I get Rth:
View attachment 111864
Removing Rl, replacing the voltage sources with shorts and starting from the left: I have 2Ω in parallel with 4Ω; then 4Ω in series; then that's in parallel with 2Ω and finally that's in series with 4Ω. It can be shown as (2Ω||4Ω+4Ω)||2Ω+4Ω; I get 60/11 Ω for this.
One tends to remember principles and not the names of those principles over the years. You are correct of course. I assumed that both had been taught together. But if not and/or the instructor is expecting the student to only use superposition and Thevenin equivalents, then it would be best to start with the Rth per The Electricians method and use superposition to get Vth. In any case the OP has already solved that portion of the problem.To be perfectly succinct, this circuit can not be solved in that manner using only Thevenin. In fact, doing it from left to right means the very first step uses Norton's theory not Thevenin. Too bad these two often get lumped into Thevenin so he gets all the credit and Norton almost none unless someone happens to mention him.
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