Kirchhoff's first rule of any junction of several circuit element in an electric circuit is based on the law of conservation of:
Mass
Charge
Linear momentum
Energy
The Correct Option is B
Solution and Explanation
Kirchhoff's first rule of any junction of several circuit elements in an electric circuit is based on the law of charge conservation.
Kirchhoff's first rule:
This law is also known as the junction rule or current law (KCL). According to it the algebraic sum of currents meeting at a junction is zero i.e. Σi=0.
In a circuit, at any junction, the sum of the currents entering the junction must be equal the sum of the currents leaving the junction i.e., i1+i3=i2+i4
This law is simply a statement of “conservation of charge” as if current reaching a junction is not equal to the current leaving the junction, the charge will not be conserved.
Hence, the correct option is (B).
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Concepts Used:
Kirchhoff's Laws
Kirchhoffs Circuit Laws allow us to solve complex circuit problems.
Kirchhoff's First Law/ Kirchhoffs Current Law
It states that the “total current or charge entering a junction or node is exactly equal to the charge leaving the node as it has no other place to go except to leave, as no charge is lost within the node“.
Kirchhoff's Second Law/ Kirchhoffs Voltage Law
It states that “in any closed loop network, the total voltage around the loop is equal to the sum of all the voltage drops within the same loop” which is also equal to zero.