INTRODUCTION

Kirchhoff’s laws, the current law (which applies the concept of charge conservation) and the voltage law (which applies the principle of energy conservation), give a systematic way to addressing complicated circuits.

Kirchhoff’s current law is crucial in contemporary measurement techniques and is commonly used in electrical engineering to establish how current is distributed in a circuit, is critical in electrical circuit design, and is critical in detecting flaws or abnormalities in electrical systems.

The Kirchhoff’s voltage law is frequently used in mesh analysis, which is a technique for analyzing circuits with many loops.Engineers may use this rule to better understand voltage distribution, evaluate complex circuits, measure voltage, and ensure proper circuit performance.In this discussion, we will look at determining the unknown values, illustrating how they might be used in practice.

KIRCHHOFF’S FIRST LAW

Kirchhoff’s first law states that « IN AN ELECTRIC CIRCUIT, THE ALGEBRAIC SUM OF CURRENT AT ANY JUNCTION IS ZERO ».

TOTAL CURRENT ENTERING A JUNCTION EQUALS TOTAL CURRENT LEAVING THE JUNCTION.

Current flowing towards the junction is taken as POSITIVE and current flowing away from the junction is taken as NEGATIVE.

KIRCHHOFF’S SECOND LAW

Kirchhoff’s subsequent(second) law is otherwise called Voltage law (OR) Loop law.

This law depends on LAW OF CONSERVATION OF ENERGY.

Kirchhoff’s subsequent law expresses that  » THE ALGEBRAIC SUM OF ALL THE POTENTIAL DIFFERENCES ALONG A CLOSED LOOP IS ZERO ».

• Kirchhoff’s laws are used to calculate the current through a resistor (use Kirchhoff’s current law to write an equation that sums the current entering and leaving the resistor), 
• voltage across a capacitor (use Kirchhoff’s current law and Kirchhoff’s voltage law to write an equation that sums the voltage drop around the capacitor), and
•  power dissipated by a resistor (use Kirchhoff’s current law and Kirchhoff’s voltage law to write an equation that relates the power voltage and the resistance of the resistor and to determine  the behaviour of  a circuit under different conditions.

NUMERICAL ON KIRCHHOFF’S LAW

NUMERICAL

Calculate the current through the galvanometer when a potential difference of 10 V maintained across AC as shown in the image.

SOLUTION

MODIFIED CIRCUIT

« KIRCHHOFF’S SECOND LAW – CONVENTIONS »

• Accept any course (direction) as the heading of traversal (direction of traversal). (Either clockwise or anticlockwise)

• EMF of the cell is POSITIVE in the event that the bearing of the crossing (direction of the traversal) is from its NEGATIVE terminal to POSITIVE terminal. (NPP)

• EMF of the cell is NEGATIVE assuming the heading of the crossing (direction of the traversal) is from its POSITIVE terminal to NEGATIVE terminal of the battery. (PNN)

• The IR item is taken as POSITIVE on the off chance that the resistor is crossed a similar way as the expected to be current. (If the resistor is traversed in the same direction as the assumed current.)

KIRCHHOFF’S LAW NUMERICAL:

FOR THE CLOSED LOOP ‘BADB’

KIRCHHOFF’S LAW NUMERICAL:

FOR THE CLOSED LOOP ‘BCDB’

KIRCHHOFF’S LAW NUMERICAL:

FOR THE CLOSED LOOP ‘ADCEFA’

KIRCHHOFF »S LAW NUMERICAL:

« SOLVING THE EQUATIONS » 

 

CONCLUSION

Kirchhoff’s laws, based on the notion of charge and energy conservation, enable us to understand and predict the behavior of electrical circuits.Kirchhoff’s laws are useful tools for electrical engineers and other circuit specialists.These guidelines are used to solve complex circuit problems and to construct electrical systems.

Kirchhoff’s laws allow us to calculate current, voltage, and resistance in a circuit.Engineers and students can improve their abilities to solve complicated circuits and create efficient electrical systems by exercising these rules.Kirchhoff’s rules remain an important framework in the field of electrical engineering for technological and innovative breakthroughs.

Links to this topic

Kirchhoff’s First law

Kirchhoff’s Second Law

Kirchhoff’s law numerical