ESE Mechanical Engineering :Important and Most Asked Technical questions during interviews

By BYJU'S Exam Prep

Updated on: September 25th, 2023

While appearing for any interview, the first round is usually about self-introduction. The interviewer asks some personal questions to the aspirant to get a brief about candidate’s background. After a brief self-introduction, the interviewer asks some technical questions related to candidate’s branch.

Engineering  Services Examination (ESE) is one of the most prestigious examinations conducted in India by UPSC. It gives an opportunity to engineers to work under the government of India and designated as Class – 1 officer in public sectors such as Indian Railways, Power, Telecommunications, Central Water Engineering, Defense service of Engineers, Central Engineering Service, etc. The ESE examination paper is conducted for four branches: Mechanical Engineering, Electronics & Telecommunication Engineering, Electrical Engineering, and Civil Engineering.

Here we are providing all important technical questions which were asked in previous ESE interviews and will be useful for upcoming  ESE 2021 interview.

  • Which one is more efficient Four stroke engine and a two stoke engine and why?
  • Difference between Flywheel and Governor
  • Difference btw nozzle and diffuser?
  • Difference between bending moment and twisting moment?
  • Difference between induced draft cooling tower& natural draft cooling tower?
  • Difference between Performance and Efficiency?
  • Difference between PERT and CPM.
  • Difference between stress and pressure?
  • Difference between refrigerator and air conditioner?
  • Difference between turbo propulsion and turbojet?
  • Different types of dynamometers?
  • Do India have drones? what are drones?
  • Draw the diagram of diesel cycle?
  • Draw the Merchant circle diagram and explain it?
  • Draw the p-v diagram of Rankine cycle?
  • During the design of a friction clutch what are the considerations that should be made?
  • Explain Brayton Cycle and Otto Cycle?
  • Explain fluid coupling, fluid torque converter?
  • Explain the difference between projectile motion and rocket motion?
  • Explain the difference between projectile motion and rocket motion?
  • Explain two stroke and four stroke engine.
  • Explain difference between hot rolling and cold rolling?
  • Explain, why re-heater is used in gas turbine?
  • Find the material which conduct faster heat among steel, copper and brass.
  • For what purpose venturimeter is used?
  • Give some difference between Antifriction Bearing and Journal Bearing?
  • How a Diesel Engine Works as Generator?
  • How a pressure cooker works?
  • How braking is done in ship?
  • How can a square section cut in lathe?
  • How nozzle work?
  • How screw jack works?
  • How to measure temperature of Bearing?
  • If a body critically damped, what will happen to its motion?
  • Interpret a Stress vs. Strain Curve.
  • Is cast iron weldable?
  • On what basis can sliding contact bearings be classified?
  • Poisson’s Ratio is Higher in, Rubber/Steel/Wood?
  • Tell any four properties of steel?
  • Tell us boiler thickness formulas
  • Tell us different types of hardness testing method.
  • Tell us forecasting models? Explain Delphi method.
  • Types of refrigeration and where they are used?
  • What are different failure theories of solid material and what is distortion energy failure?
  • What are different types of paintings?
  • What are the Advantages and Disadvantages of using LPG in Car?
  • What are the different theories of failure under static load, explain briefly?
  • What are the different types of bearings?
  • What are the different types of couplings and its applications?
  • What are the different welding defects?
  • What are the effects of boiler scale formation?
  • What are the pollutants or emission from vehicle?
  • What are the rules that must be kept in mind while designing castings?
  • What are the safety devices in railway?
  • What is air density?
  • What is an arc welding and tell its different types?
  • What is CMM?
  • What is Cotter joint?
  • What is critical damping ratio? What is the physical significance?
  • What is damper?
  • What is FMS? Tool signature?
  • What is heat treatment process?
  • What is Hook`s Law ?
  • What is the difference between ductile and brittle material.
  • What is Hydrodynamic Cavitation?
  • What is Hydrostatic System?
  • What is inventory? How it can be maintained?
  • What is meant by gear ratio?
  • What is meant by vibration isolation in machines?
  • What is Operating Pressure?
  • What is painting?
  • What is primary and secondary balancing?
  • What is process capability?
  • What is shot peening?
  • What is six sigma concept?
  • What is specific gravity of a fluid?
  • What is stress concentration factor?
  • What is the calorific value of CNG, ethylene?
  • What is the Density of mild steel?
  • What is the density of petrol?
  • What is the difference between a Shaper machine and a Planner machine?
  • What is the difference between drilling and boring?
  • What is the difference between Fan and Blower?
  • What is the difference between lathe & milling machine?
  • What is the difference between thin and thick cylinder?
  • What is the different type of braking used in automobile?
  • What is the effect of reheater in the gas turbine?
  • What is the engineering?
  • What is the mechanical?
  • What is the position of Piston Ring?
  • What is the process flow diagram?
  • What is the shape of bending moment of the UDL?
  • What is the significance of line of action in gear?
  • What is the advantage of disc brake over drum brake?
  • What is value engineering?
  • What is water hammer?
  • What is crankshaft?
  • what kind of  technology used to reduce emission?
  • What kind of materials should be used for shafts manufacturing?
  • What will happen if the speed of the centrifugal pump is doubled?
  • What is the order of firing in 4-cylnder engine?
  • What is the Mach Number and its importance?
  • What is pure shear and pure bending?
  • When Crude Oil is Heated, Which Hydro Carbon comes first?
  • Where cavitation occurs in hydraulic machines?
  • Where did nuclear disaster take place?
  • Where half nut is used?
  • Which is hard material Cast Iron or Mild Steel?
  • Which is heavier 1kg Cotton or 1kg Iron?
  • Which one have density petrol or water?
  • Which one is stronger: thick steel wire or thick steel wire?
  • Which operation converts the square block into circular shaft?
  • Which type of brake used in railway?
  • Which type of coaches ICF manufactured
  • Which type of flow when the water falls from a tap?
  • Which type of springs used in railway wagons?
  • Who invented a four stroke engine?
  • Why are the heavy vehicles made by diesel engine?
  • Why is carbon added to iron?
  • Why is the Entropy decreases with increase in temperature?
  • Why is the Centrifugal Pump called High Discharge pump?
  • Why is centrifugal casting developed for manufacturing hollow casting?
  • Why should a chain drive be used over a belt or rope driven drive?
  • Why the rail in form of I-beam?
  • Why there is concern for setting nuclear power plant?
  • Why is Throttle valve used in stream engine?
  • Working & advantage of four strokes IC engine?

Some of the commonly asked questions in IES are:-

  1. Why do you want to join IES/ESE?
  2. Why do you want to join some particular department for e.g. Railways?
  3. Tell a brief about your current firm?
  4. Are you not satisfied with your current job?
  5. How you being an IES officer will help the nation?
  6. Why you want to join Civil Service?
  7. Tell us about yourself?

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