About this previous year paper
This examination paper evaluates students’ conceptual understanding and analytical skills in fundamental electrical engineering topics, including circuit analysis, AC fundamentals, machines, transformers, power systems, and electrical safety. The paper is divided into three structured sections (A, B, and C) to test knowledge ranging from basic definitions to applied numerical problems and derivations.
SECTION A — Short Answer Questions (2 × 7 = 14 Marks)
This section contains seven compulsory short questions, each aimed at testing foundational knowledge.
Topics Covered:
1. Basic Electrical Sources & Elements
Difference between ideal and practical voltage sources
Unilateral vs bilateral elements
Active vs passive elements
2. AC Circuit Concepts
Average power consumed by a pure inductor
Resonant frequency and Q-factor of series RLC circuit
3. Magnetic & Electromagnetic Concepts
Inductance calculation from rate of change of current
4. Electrical Machines
Role of slip rings in 3-phase induction motors
5. Electrical Installation
Common problems in wiring and electrical installation systems
This section evaluates conceptual clarity and basic definitions.
SECTION B — Descriptive Questions (7 × choose any 3 = 21 Marks)
Students must attempt any three questions. These questions require explanation, circuit analysis, calculations, and reasoning.
Topics Covered:
1. Network Analysis
Current calculation using nodal analysis
Understanding of DC and AC circuit principles
2. Waveform Characteristics
Form factor and peak factor for half-wave rectified signal
3. Transformer Performance
Efficiency at full load (0.8 pf lagging) and at half load (unity pf)
Iron loss and copper loss considered
4. Induction Motor
Working principle
Torque-slip characteristics
5. Batteries
Primary and secondary batteries
Working principle of a specific secondary battery (e.g., lead-acid battery)
This section tests students’ analytical and explanatory approach with numerical and descriptive methods.
SECTION C — Long Answer Questions (7 marks each)
Each block contains two questions. Students must attempt one from each block.
Question 3 – Mesh & Nodal Analysis
3(a) Numerical Analysis
Calculate current across a given resistor using
Mesh Analysis (loop currents)
Nodal Analysis (node voltages)
3(b) Theory Question
Procedure of mesh analysis with an example
Evaluates understanding of fundamental network theorems and analysis methods.
Question 4 – AC Circuits & Three-Phase Systems
4(a) Bandwidth & Resonance
Derivation of expressions for:
Bandwidth
Upper half-power frequency
Lower half-power frequency
4(b) Three-Phase Star Circuit
Relation between line and phase voltages
Calculation of:
Line current
Power factor
Active and reactive power
Tests AC circuit theory, three-phase analysis, and formula derivation skills.
Question 5 – Transformers
5(a) Transformer Equivalent Circuit
Calculate:
Equivalent resistance and reactance referred to primary
Total copper loss
5(b) Phasor Diagram
Ideal vs practical transformer at no-load
Drawing and interpretation
Focus: transformer theory, modeling, and phasor representation.
Question 6 – DC Machines & Single-Phase Motors
6(a) DC Shunt Motor Torque & Speed
Torque equation derivation
Numerical speed calculation using given parameters
6(b) Single-Phase Induction Motor
Why it is not self-starting
Starting methods (capacitor start, split-phase, shaded pole)
Explain one method in detail
Assesses understanding of machine theory and mechanical-electrical relationships.
Question 7 – Electrical Safety & Protection
7(a) Safety Devices
Explanation with diagrams:
Earth Leakage Circuit Breaker (ELCB)
Miniature Circuit Breaker (MCB)
7(b) Earthing & Grounding
Difference between earthing and grounding
Different methods of earthing:
Plate earthing
Pipe earthing
Rod earthing
This section focuses on practical electrical installation and safety systems.
Overall Purpose of the Question Paper
This examination evaluates the student’s ability to:
Understand fundamental electrical laws and elements
Apply circuit analysis techniques (nodal, mesh, AC analysis)
Analyze transformer and machine performance
Interpret waveforms and AC characteristics
Perform calculations for power, efficiency, and resonance
Understand transformer and motor working principles
Demonstrate knowledge of electrical safety systems
The question paper ensures that engineering students develop a strong and practical foundation in electrical engineering, preparing them for more advanced subjects like power systems, electrical machines, and control systems.