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I2 = 3/5 ?? µA? mA? A? ...i2=3/5
In the same way: set up the equations, solve for R.How to find out the resistance R?
From the circuit, I can't find out the current or voltage across the R because R is unknownIn the same way: set up the equations, solve for R.
Show us your effort.
.
What do you mean?Doing a quick calculation shows that this diagram has no single solution. You can express voltage across the 2 Ω resistor and current through it only as a function of R. As in V(2Ω) = f(R).
Or vice versa.
R.
Arrow is indicate the direction of current, not the value of current. If I apply the kcl at left node of 2 Ohm resistor. I can't set the equations because there are two unknown values of currentUnless one other current is given. E.g. current through R as indicated by the arrow on the wire leading to R.
From the circuit, I can't find out the current or voltage across the R because R is unknown
I think the possible conditions
Current through 1Ω
I=50v/1Ω
I=50/1 A
voltage across 1Ω
V=50A*1Ω=50v
Now how to find out current and voltage for 2Ω
As Ratch elaborated: You can chose any value of R and will get a resulting distribution of currents and voltages whcih can be expressed by a set of equations as in V(2Ω) = f(R) where f(R) is a rational function of R.What do you mean?
Let's suppose voltage across R is V
Then current throw through R resistor should be Ir=V/R
current I1=4A given
Current through the 2 ohm resistor is I2
Apply kcl
I1=Ir+I2
4A=V/R+(V50)/22 R2
If the current through 1ohm resistor is I3
I4 is current from 50 volt source
Again from the kcl
I2+I4=I3
(V50)/2+I4=50
Here I have two equations but I don't understand how to solve
I tried to set equations
4A=V/R+(V50)/2
(V50)/2+I4=50
Is it correct?
From the equations, I don't understand how to find out voltage across R
Do you mean, the value of R may be anything 2, 4, 8 ohms etc. I have to take one value then I have to find voltage and current through RPick any R and the voltage can be calculated. Do you have a sense of what is going on?
Ratch
Yes, that is correct. The independent current source is going to output 4 amps regardless of what the value of R is. Likewise, the independent voltage source is going to output 50 volts regardless of what R is. All the other resistors are fixed in value. The only way you can change the voltage across R, or the current through R, is to change the value of R. As an extreme case, consider R = 0 . The equation you found gives a voltage value of 0 volts. Makes sense, right? Now, consider R = infinity. The equation gives a value of 58 volts. Once you know the voltage across R, you can find the currents in the rest of the circuit.Do you mean, the value of R may be anything 2, 4, 8 ohms etc. I have to take one value then I have to find voltage and current through R
I did as you said
If R= 2 ohms then voltage across 2 ohms resistor is 29 volts