Kichoffs law ppt presentation

1. Kirchhoff’s Laws
Name:-Basir Khan
Regd.No:-220301120209
Sec:-D

2. Content:
 Kirchhoff’s first laws (KCL)
 Kirchhoff’s second laws(KVL)
 Terminologies
 Problems
 Conclusion

3. Kirchhoff's First Law –The Current Law, (KCL)
• Kirchhoff's Current Law or KCL, 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“.
In other words the algebraic sum of all the currents entering and leaving a
node must be equal to zero, I(exiting) + I(entering) = 0.This idea by Kirchhoff is
commonly known as the Conservation of Charge.
Sign Convention :
For an instance choose all the incoming current at a node as positive and outgoing
current as negative.

4. Kirchhoff's Second Law –TheVoltage Law, (KVL)
Kirchhoff'sVoltage Law or KVL, 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. In
other words the algebraic sum of all voltages within the loop must be equal to zero.This idea by
Kirchhoff is known as the Conservation of Energy.
 Sign Convention:
Positive voltage sign i.e. potential rise if current pass from negative
terminal to positive terminal of the element and negative sign i.e. voltage drop
if current pass from positive to negative terminal.

5. Terminologies :
• Circuit – a circuit is a closed conducting path through which an electrical current flows.
• Node – a node is a point in a circuit where two or more circuit element are connected.
• Branch – a branch is the part of a network which lies between two nodes.
• Loop – a loop is a closed path in a circuit in which no circuit element or node is encountered more
than once.
• Mesh – It is a loop that contain no other loops within it.
 When analyzing either DC circuits or AC circuits using Kirchhoff's Laws a number of definitions
and terminologies are used to describe the parts of the circuit being analyzed such as: node,
Circuit, , branch, loop and mesh.These terms are used frequently in circuit analysis so it is
important to understand them.

6. Problem:-
Find the value of I1 assuming
that I2 =5A I3 =1A I4=3A ?
Solution:-
Applying kcl ,we get
=> I1 =I2+I3+I4
=>I1=5A+1A+3A
=>I1=9A

7. Problem:-
Find the voltage (v)
using kvl law?
Solution :-
Applying kvl ,we get
=>v-(3x4)-(2x3)=0
=>V-12-6=0
=>V=18V

8. Conclusion
• By knowing and using Kirchhoff’s Laws we can simplify our calculations and
reduce more amount of mathematics in solving for circuits.

9. THANKYOU