Why Is the Current Negative in This Circuit Division Equation?

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The current I is negative because it flows in the opposite direction as indicated by the circuit's configuration. The equation I = (-2)(6||3)/(6) reflects this directionality. Kirchhoff's Laws are essential for understanding current flow in circuits, ensuring that the sum of currents entering a junction equals the sum leaving. In this case, the 2mA current from the source flows out of the junction, necessitating the same current to flow through the resistors. Understanding these principles clarifies why the current is negative in this scenario.
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Can someone tell me why the current I is negative and not positive?

Im guessing the equation should be:
I = (-2)(6||3)/(6). But why the negative sign?
 

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Well, the current has to flow in the opposite direction as indicated.

ehild
 
ehild said:
Well, the current has to flow in the opposite direction as indicated.

ehild

Are there any general rules to follow because I'm sure most circuits won't be as obvious
 
There are Kirchhoff's Laws.

The 2mA current of the current source flows out of the top junction, so the same current has to flow in through the resistors. The sum of the currents flowing in is equal to the sum of the outflowing currents according to Kirchhoff's Current Law. So the current flows upward through the 2 kΩ resistor.

ehild
 

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