LPSC Scientist/Engineer SC 03/2026: Written Test Pattern and What to Revise
LPSC/03/2026 has a three-part written test: 60 discipline MCQs with one-third negative marking, 20 marks of aptitude, and 20 marks of descriptive questions. You need 50 percent in every part.
The advertisement for LPSC/03/2026 prints the written-test pattern but not a chapter list. The pattern matters more than usual here, because each part has its own cutoff. Eligibility, dates and the fee refund are on the recruitment page.
The pattern in numbers
| Part | What it tests | Questions | Marks | Time | Wrong answer |
|---|---|---|---|---|---|
| A | Your discipline | 60 MCQs | 60 | 75 minutes | Minus one third |
| B | Aptitude | Up to 15 | 20 | 30 minutes | No penalty |
| C | Descriptive technical | As set | 20 | 30 minutes | No penalty |
| Total | 100 | 135 minutes |
Part A gives you 75 seconds a question. With one third deducted for a wrong answer, a random guess among four options gains nothing on average. Guess only when you can rule out at least one option.
The cutoff that catches people
To be shortlisted for interview you need 50 percent in each part and 50 out of 100 overall. That means at least 30 in Part A, 10 in Part B and 10 in Part C. A candidate with 50 in Part A and 8 in Part C fails, even with 68 overall.
Shortlisting is 1:5, with at least 10 candidates for each post where that many qualify. For a single vacancy, that usually means 5 to 10 people in the interview room. The interview needs 60 percent, and it counts for half of the final merit.
Part A by post code
Post 820, Welding. The job is research on welding high-nickel alloys, stainless steels and non-ferrous metals. Revise:
- welding metallurgy: the heat-affected zone, sensitisation and intergranular corrosion in austenitic stainless steel, hot cracking in nickel alloys, and the role of delta ferrite
- processes: GTAW, GMAW, plasma arc, electron beam and laser welding, friction stir welding, and when each is chosen
- weld defects and inspection: porosity, lack of fusion, radiography, ultrasonic and dye-penetrant testing
- heat input, preheat and post-weld heat treatment, and residual stress and distortion
Post 821, Turbo Machinery. The job is design, CFD, testing and performance analysis of turbo machines in launch vehicles, in practice turbopumps. Revise:
- Euler's turbomachine equation, velocity triangles, and specific speed
- centrifugal and axial pumps and turbines, cavitation, NPSH, and inducers
- dimensional analysis and similarity laws
- compressible flow basics, boundary layers, and turbulence modelling in CFD
Post 822, Power Electronics. The job is high-power, high-frequency converters, lightweight converters for small satellites, and BLDC motor drives. Revise:
- DC-DC converters (buck, boost, buck-boost, flyback, forward, full bridge), duty-cycle relations, and continuous and discontinuous conduction
- switching devices: MOSFET, IGBT, SiC and GaN, and switching and conduction losses
- magnetics: inductor and transformer design, core loss, and soft switching
- BLDC motors, commutation, PWM control, and control loops and stability
Part B and Part C
Part B is up to 15 aptitude questions for 20 marks, with no negative marking. The advertisement lists numerical, logical, diagrammatic, abstract and deductive reasoning. Because there is no penalty, answer every question.
Part C is 20 marks of descriptive technical writing in 30 minutes. Expect short design or explanation questions from the job description of your post code. Practise writing a clear half-page answer with one labelled sketch or equation. You need 10 of the 20 marks.
Questions on the eligibility rules and the core of each discipline are on the practice page.
Frequently Asked Questions
No. It gives the three parts, their marks and time, and the aptitude areas. The discipline topics below follow the job description printed for each post code and the core of the ME or MTech specialisation it asks for.
No. You need 50 percent in Part A, Part B and Part C separately, and 50 out of 100 in total.
Half. Final merit is 50 percent written test and 50 percent interview, and the interview itself needs 60 percent.
Keshav founded StudentUpdate.in and edits every recruitment notice, syllabus page and practice set the site publishes. Each notice is read from the issuing body's PDF or portal before it goes live; dates, fees, vacancy tables and eligibility rules are copied from that document, not from other websites.