Application of Circuit laws (KCL and KVL)

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hms.tech
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Homework Statement


Calculate the resistance of this combination of resistors

Homework Equations



V=IR

The Attempt at a Solution



By using KVL :

V= 3[itex]I_{5}[/itex] = [itex]I_{2}[/itex] = 2[itex]I_{4}[/itex]
I = [itex]I_{1}[/itex] + [itex]I_{2}[/itex]
[itex]I_{3}[/itex] = [itex]I_{2}[/itex] + [itex]I_{4}[/itex]
[itex]I_{1}[/itex] = [itex]I_{5}[/itex] + [itex]I_{4}[/itex]
I = [itex]I_{3}[/itex] + [itex]I_{5}[/itex]Now the final result could be obtained by the simple equation : R =V/I (this is where my progress stagnates)
 
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Your first equation relates currents I2, I4, and I5 to the potential across the circuit. Now, if you take your last equation and make substitutions so that you express I in terms of those same currents in the first expression, I think you'll get somewhere.
 
You mean like this :

I = [itex]I_{5}[/itex] + [itex]I_{2}[/itex] + [itex]I_{4}[/itex]

Thus R = V/I

that does not solve the problem ...
 
hms.tech said:
You mean like this :

I = [itex]I_{5}[/itex] + [itex]I_{2}[/itex] + [itex]I_{4}[/itex]

Thus R = V/I

that does not solve the problem ...

But you can substitute your expressions for those currents from your first equation...