# kcl and kvl what is the difference

I am very confused in the terms of what is the actual difference between kcl and kvl?

I don't want to have a question on a test and not know where to apply kcl and where to apply kvl?

• You can use either method for tests if they don't specifically ask for a method. By doing many practice problems, you will be able to make a good guess as to which method is better for a given circuit.
– AJN
Oct 28, 2020 at 4:41
• KVL tends to focus more on currents; KCL more on node voltages. If you are solving for a BJT CE amplifier stage's quiescent base current then perhaps KVL is a little more direct. Both approaches get you similar results, applied similarly, though. And sometimes you find yourself applying both to the same circumstances in order to get the variables you want solved.
– jonk
Oct 28, 2020 at 5:10

## WHAT IS KVL AND KCL?

KVL and KCL are two fundamental laws derived from the conservation of charge and conservation of energy laws and applied to circuits. These laws are used to develop equations for circuit analysis

Kirchhoff's Voltage Law (KVL) Kirchhoff's voltage law states that the algebraic sum of the voltages around any loops in a circuit is always zero.

Kirchhoff's Current Law (KCL) Kirchhoff current law states that the algebraic sum of all currents entering a node of a circuit is always zero.

## WHEN AND WHERE TO USE KVL/KCL?

Loop/mesh and nodal analysis are methods of analysis that are used to find the unknown (voltage or current) in a circuit.

Node Analysis Most useful for when we have mostly current sources Node analysis uses KCL to establish the equations for voltages

Loop/Mesh Analysis Most useful when we have mostly voltage sources Mesh analysis uses KVL to establish the equations for current.

## Source: What is the difference and relation between KVL, KCL, loop and nodal analysis?

• The KVL diagram would be more useful if it showed at least one voltage source acting in the opposite direction to the others.
– Chu
Oct 28, 2020 at 9:35
• Dwij Mistry - Hi, Your answer is just an uncredited copy & paste of Harsh Sharma's answer here on Quora: "What is the difference and relation between KVL, KCL, loop and nodal analysis?". Such plagiarism is not welcome here. It says here in the help center: "Do not copy the complete text of external sources; instead, use their words and ideas to support your own. And always give proper credit to the author [...]". Please don't plagiarise. Oct 28, 2020 at 14:51
• @Dwij Can you please provide a source for this? It appears to be a direct copy, if you are the original author then please provide a source for the first post. Otherwise it is plagiarism. Oct 28, 2020 at 16:19
• @VoltageSpike I am really sorry for this I don't know any rules so please forgive me. I assure you I will never do this again. Oct 29, 2020 at 4:53
• @DwijMistry No problem, or need to be sorry, just make sure sources are documented. Its just good practice and to help other people remember. Thanks Oct 29, 2020 at 4:58