You need to pay attention to the direction of the currents as you do your "KVL walk" around the circuit. For example, ##I_3## is flowing down through ##R_3##, so as you "walk over" ##R_3## going clockwise around the circuit you'll see a rise in potential.Pochen Liu said:
Is this because if I go 'walk over' instead of using the voltage it will add? since it's coming from the other direction, therefore I need to change it's mathematical sign around right?gneill said:
Right, you need to account for the current directions. If you "walk" in the same direction of the current you'll see a potential drop across the resistor. If you "walk" against the direction of the current you'll see a potential rise.Pochen Liu said:
Kirchoff's law, also known as Kirchoff's circuit laws, are two fundamental principles in circuit analysis used to calculate the voltage and current in a circuit. These laws are based on the conservation of energy and charge, and are commonly used in electrical engineering and physics.
The two laws in Kirchoff's law are the Kirchoff's current law (KCL) and Kirchoff's voltage law (KVL). KCL states that the sum of currents entering and exiting a node in a circuit must be equal to zero. KVL states that the sum of voltage drops and gains in a closed loop in a circuit must also be equal to zero.
To apply Kirchoff's law in a circuit, you must first identify all the nodes and closed loops in the circuit. Then, use KCL to write an equation for each node, setting the sum of currents equal to zero. Use KVL to write an equation for each closed loop, setting the sum of voltage drops and gains equal to zero. Finally, solve the equations simultaneously to find the values of voltage and current in the circuit.
Yes, Kirchoff's law can be applied to any type of circuit, whether it is a simple series or parallel circuit, or a more complex network of interconnected components. These laws hold true for both DC and AC circuits.
Kirchoff's law assumes ideal conditions, such as negligible resistance in wires and perfect components. In reality, these conditions do not exist, and there may be some errors in the calculations due to these discrepancies. Additionally, Kirchoff's law is based on linear circuits, so it may not be applicable to non-linear circuits.
