Question

State Kirchhoff's laws.

Answer 1

Kirchhoff's laws are fundamental principles used in electrical circuit analysis. There are two main laws:

1. Kirchhoff's Current Law (KCL):

This law states that the total current entering a junction (or node) in a circuit is equal to the total current leaving the junction. In other words, the sum of all currents at a node is zero.

Mathematically:  
\[
\sum I_{\text{in}} = \sum I_{\text{out}}
\]
or  
\[
\sum I = 0
\]
This is based on the principle of conservation of electric charge.

2. Kirchhoff's Voltage Law (KVL):

This law states that the sum of all the voltages around any closed loop or circuit is zero. This means that the total energy gained by charges (through sources like batteries) is equal to the total energy lost (through resistors, capacitors, etc.) as they move around the loop.

Mathematically:  
\[
\sum V = 0
\]
The sum of the voltage drops and voltage rises around a loop must be zero. This is based on the principle of conservation of energy.

In simpler terms:

1. KCL deals with current and ensures it is conserved at any node in the circuit.
   

1. KVL deals with voltage and ensures energy is conserved in a loop.
   

Both laws are extremely helpful in analyzing complex circuits, whether in DC or AC systems.