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# [SOLVED]What is the value of currents I1 and I2 in the circuit??

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#### SanjKrish

##### Member level 3

Does I2 = 0 mean there will be no current flowing through the 5Ω resistor??
How could it be possible??
It would mean that there is no V2 in the circuit

First need to see a simple circuit.
Voltage is a difference between two points, and in this case for R2 difference is zero, so no current into. Later no matter what resistors we add, the situation doesn’t change.

#### Attachments

• voltage difference.GIF
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This is mainly the effect that we are dealing with an ideal voltage source, so the internal resistance of an ideal voltage source is zero. In theory no matter if we have placed also a resistor in parallel for V1, the voltage will remain the same. In practice no real voltage source is ideal; all have a non-zero effective internal resistance, and none can supply unlimited current. See the example attached.

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• example real source.GIF
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If KVL is applied, the equations seems to be quoted incorrectly. There can't be contribution of I1 and I2 in both the equations. Just keep the currents I1 and I2 specific to loops independently. They will come out to be 2Amps and 1Amps respectively.

-kjs

They will come out to be 2Amps and 1Amps respectively.
-kjs
:roll:
No way, first we have
5(I1+I2) + 5 I2=10
and in the same time
5(I1+I2) = 10
this mean
5 I2= 0
I2= 0
QED

mister_rf,
Your example seems to be bit confusing for me..

Anyways after thinking for sometime I just understood the thing

Yes I2 = 0 and wats wrong in it??
When I tried the ckt with V2=9V instead of 10, I got the values I1=2.2 and I2=-0.2
and with V2=11V , I1=1.8 and I2=0.2

So, its natural that when V2 happens to be 10V the ckt balances by having no current pass R2..

Try the Ohm's law.
It states that the voltage drop, V, across any resistive element is proportional to the current , I, flowing through it.
Further, the constant of proportionality is the resistance, R, of the element.
In our example across the resistor R2, the voltage drop = 0 so the current is 0.

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mister_rf could you please explain why the voltages are 9.81V and 9.99627V respectively. I am a complete beginner.
Thanks
Jack

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