Electrical Networks

Ohm's Law:

Kirchoff's Laws

1. Conservation of Energy
2. Conservation of Charge

From the upper loop, we start on node . The battery gives a voltage gain of 5, then a loss of at the resistor and at the resistor.

Similarly, for the lower loop

Applying the conservation of charge gives , so

Note that if we start at node , we obtain the same equations.

Note that on an exam, we won'd be asked to go past this step.

So , , and . is negative, which means the direction shown in the diagram above is wrong.