1. Current Divider Rule and KCL
Lecture 6
A.V.Ramachandran
03-Nov-2022
(ECE and CCE)

2. Syllabus
• Unit 1 Introduction to Electrical Engineering, Current and Voltage sources, Resistance, Inductance
and Capacitance; Ohm’s law, Kirchhoff’s law, Energy and Power – Series parallel combination of R,
L, C components, Voltage Divider and Current Divider Rules – Super position Theorem, Network
Analysis – Mesh and Node methods-
• Unit 3 PN Junction diodes, VI Characteristics, Rectifiers: Half wave, Full wave, Bridge. Zener
Diode- characteristics – regulator design, Optoelectronic devices. BJT – characteristics and
configurations (CE) , Transistor as a Switch. Junction Field Effect Transistors - operation and
characteristics, Thyristor (SCR)– Operation and characteristics. Fundamentals of DIAC and TRIAC.
555 Timer, Integrated circuits. Operational Amplifiers – Inverting and Non-inverting amplifier –
Instrumentation amplifiers.
• Rest of Unit-1: Faraday’s Laws of Electro-magnetic Induction, Magnetic Circuits, Self and Mutual
Inductance, Generation of sinusoidal voltage, Instantaneous, Average and effective values of
periodic functions, Phasor representation. Introduction to 3-phasesystems, Introduction to
electric grids.
• Unit 2 Electrical Machines: DC Motor: Construction, principle of operation, Different types of DC
motors, Voltage equation of a motor, significance of back EMF, Speed, Torque, Torque-Speed
characteristics, Output Power, Efficiency and applications. Single Phase Transformer:
Construction, principle of operation, EMF Equation. Regulation and Efficiency of a Transformer.
Induction Machine: Three Phase Induction Motor: Construction and Principle of Operation, Slip
and Torque, Speed Characteristics. Stepper motor: Construction, principle and mode of operation.

3. Text Books and References
• Textbook(s)
• Edward Hughes. “Electrical and Electronic Technology”, 10th Edition, Pearson Education Asia,
2019.
• D. P. Kothari, I J Nagrath, “Electric Machines”, 5th Edition, Tata McGraw Hill, 2017.
• A. P. Malvino, “Electronic Principles”, 7th Edition, Tata McGraw Hill, 2007.
• References
• S. K. Bhattcharya, “Basic Electrical and Electronics Engineering”, Pearson, 2012.
• Vincent Del Toro, “Electrical Engineering Fundamentals”, Prentice Hall of India Private Limited,
2nd Edition, 2003.
• David A. Bell, “Electronic Devices and Circuits”, 5th Edition, Oxford University Press, 2008.
• (Michael Tooley B. A., “Electronic circuits: Fundamentals and Applications”, 3rd Edition,
Elsevier Limited, 2006.
• K. S Suresh Kumar, “Electric Circuits and Networks”
• W.H. Hayt, “Engineering Circuit Analysis” Mcgraw Hill, 2012

4. Electrical and Electronics Engineering
Faraday’s Law and Magnetic
Circuits
AC Generation
and Distribution
Transformer
DC Motor
Induction
Motor
Stepper
Motor
Components
R,L and C Semiconductor Devices
Low Power Devices
PN Junction
Rectifiers
BJT
Switch
JFET IC
555
Timer
OPAMP
Amplifiers
High Power Devices
Thyristor, Diac and
Triac
Laws/Theorems/Analysis/
Techniques
Applications
Applications
Working Mechanism
(CO-3)
(CO-4)
(CO-1 & CO-2)
(CO-1)
(CO-4)
(CO-1)
(CO-2 & CO-4)
(CO-2 & CO-4)
Concept Map
Used to
analyse
and
design

5. Find the total resistance

11. Summary

12. Summary

13. Summary

14. Rule of Thumb
• In a series circuit, the total resistance is always greater than the
greatest resistance in the circuit.
• In a parallel network, the total resistance is always less than the
smallest resistance in the network

15. Kirchhoff’s law
• First (current) law. At any instant the algebraic sum of
the currents at a junction in a network is zero.
Gustav Kirchhoff
[Source: Wikipedia]
Electric circuits,
Optics,
Spectroscopy,
Thermochemistry
etc..

17. Law need not only apply to a junction but may also apply to a section of a network

18. If only input and output are investigated, no need to know about the middle one
(can treat as black box)

19. Current flow upwards!

20. Series-Parallel Network
Whether R2 is in parallel with R6?
Network in series!

21. Find the voltage across and power absorbed in each
resistors?

22. Kirchhoff’s Voltage Law
• At any instant in a closed loop, the algebraic
sum of the e.m.f.s acting round the loop is
equal to the algebraic sum of the p.d.s round
the loop.
William H. Hayt’s definition:
“The algebraic sum of the voltages
around any closed path is zero”
Node, Path, Loop, Branch

23. Node, Path, Loop and Branch
• Node
• A point at which two or more elements have a common connection
• Path
• If no node was encountered more than once, then the set of nodes and
elements that we have passed through
• Loop
• Closed path (start and stop nodes are same)
• Branch
• One simple element and the node at each end of the element
[William H. Hayt Book]