🎓 Candidate: Nitish Kumar
📅 Date: 13th June 2025
📍 Venue: NPCIL Interview Panel
🎯 Stream: Mechanical Engineering
🎯 Interview Overview
The NPCIL interview was conceptual, application-oriented, and cross-disciplinary, with questions drawn from core mechanical subjects. Each panel member tested technical depth, reasoning skills, and clarity of engineering fundamentals.
🔁 Initial Lesson – Subject Selection Strategy
Panel Question:
“Which subjects are your strongest?”
My Response:
I mentioned all five core subjects.
Lesson Learned:
It’s better to select 3–4 strong subjects instead of listing all. This helps the panel focus and allows deeper discussion in your areas of comfort.
❄️ 1. Heat Transfer – Location-Based Application
Question:
“Between Kanyakumari and Ladakh, where would it be more efficient to install a power plant and why?”
Discussion Points:
- Carnot Efficiency: Efficiency increases with a larger temperature difference
- Ambient Temperature: Ladakh has lower ambient temperatures → better cooling
- Cooling Water Availability: Kanyakumari may have more water access
- Balance between efficiency and feasibility
🪟 2. Heat Transfer – AC Train Window Profile
Question:
“Draw the temperature profile across a double-pane glass window of an AC train.”
Scenario Explained:
- Double-pane structure with trapped air gap
- AC inside, hot climate outside
Expected Answer:
- Temperature drops across each layer
- Non-linear profile in air gap due to thermal resistance
- Explained using Fourier’s Law and thermal conductivity difference
🧱 3. Strength of Materials (SoM)
Question:
“You have a cantilever beam with a moment at one end and a point moment at the free end. Draw the bending moment diagram and deflection curve.”
Concepts Tested:
- Superposition principle
- Moment boundary conditions
- Qualitative shape of bending moment and deflection curves
⚙️ 4. Theory of Machines (ToM)
Question:
“Design a belt drive system to transmit power from a motor to a shaft.”
Discussion Points:
- Pulley diameter and material selection
- Belt tensioning and alignment
- Velocity ratio and safety factor
- Shaft design for power transmission
🧠 Key Takeaways from the Interview
✅ Subject Strategy:
Mention only 3–4 favorite subjects for focused questioning.
🧠 Application-Based Thinking:
Be prepared for practical, real-life engineering problems, not just definitions.
📉 Diagram Practice:
Drawings are a must—practice bending moment diagrams, temperature profiles, and mechanical layouts.
🛠️ Concept Clarity:
Panels appreciate candidates who apply core principles to real-world constraints like cooling, efficiency, and materials.
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