Kirchhoff law


KVL KCL BASICS
KVL, KVL BASICS
Kirchhoff's circuit laws
FIRST LAW – KCL
KCL or Kirchhoff's Current Law is used to find a current around a node and based on the principle of conservation of electric charge implies that:
Around a node or junction the algebraic sum of incoming and outgoing current is zero.

Or
Around a node the sum of incoming and outgoing current is same.





 I1 + I2 + (- I3) + (-I4) + I5 = 0
n = no of branch current
KCL is applicable to lumped circuits only.

SECOND LAW
KVL or Kirchhoff's voltage law is use to find voltage in around a loop and based on the principle of conservation of electric energy implies that:
In any closed loop or a mesh the algebraic sum of total voltage is always zero.
Or

 In a closed loop voltage gain equals to voltage drop.

 


(-V1) + (- V2) +I1R1 + I2R2 + I3R3 + I4R4 = 0
n = no of voltage
Again KVL is applicable to lumped circuits only

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