Interview Questions

Machine Design

1. Differentiate between service factor and factor of safety.
2. Draw a typical true stress versus strain curve .
3. What is wahl’s stress factor
4. Explain hydrodynamic theory of lubrication
5. Classify welded and riveted joints.
6. Explain the term virtual number of teeth in helical and bevel gears
7. How do you specify the life of an anti friction bearing?
8. Explain the term membrane stresses in vessels under pressure

Thermodynamics

1. What are various thermodynamic systems and their basic definitions?
2. What is meant by the triple point of water?
3. Which Law of Thermodynamics is relevant when you inflate a tyre?
4. Explain a perfect gas and its properties

Thermal Engineering

1. Why don’t CI engines require spark plug?
2. What is an indicator diagram? What are its advantages? How is it different from a P-V diagram?
3. What is the difference between turbocharging and supercharging?
4. What is knocking, detonation and pre-ignition? What are the preventive methods?
5. New trends in IC engines, CDI,Ball piston, Cam less engines, GDI and VTEC
6. Explain super saturated flow in steam nozzles
7. What is reheat factor?
8. What is meant by a pulsed detonation engine?
9. Is turbocharging possible in a petrol engine? Why?

Heat and Mass Transfer

1. State Fourier’s laws of conduction in one dimension
2. Explain LMTD and NTU methods
3. Explain the concept of black body
4. Differentiate between parallel and counter flow exchangers

Refrigeration and Air Conditioning

1. Explain simple vapour compression cycle in a refrigerator
2. Which compressor is usually used in air conditioners?
3. What is ASHRAE?
4. Explain Joule-Thomson effect
5. Explain Sensible heating and cooling, superheating and Subcooling
6. What is the significance of multicompressor refrigerator system?
7. What is meant by 1 TR?
8. What is meant by sensible heat factor?
9. Differentiate between RSHF and GSHF
10. What is meant by effective temperature?

Automobile Engineering

1. During the starting of a vehicle, the exhaust smoke appears white. Why?
2. What is a differential and how does it work?
3. What are MPFI and TPFC systems?
4. Mention the common automobile specifications
5. What is SAE?
6. Certain vehicles can be started by keeping the gears engaged, while certain others cannot. Explain

Theory of Machines

1. How do you polish a ball bearing?
2. Which gear is used to obtain maximum speed ratio?
3. Explain the functions of Gyroscopes
4. What are the different types of clutches in use and their working?
5. Draw a Hooke’s joint and explain its function
6. What is the type of braking system in trains? Explain its function
7. Explain the function of a gearbox. What are the types of gearboxes?

Manufacturing Processes

1. Differentiate between a lathe and a milling machine
2. What are CNC and DNC machines?
3. How do you a machine a square cross section in a lathe?
4. What are satellites. Why cant single carbide be cut efficiently?
5. Differentiate between Upmilling and Downmilling
6. What is a self centering chuck?
7. What are the different indexing mechanisms used in conventional machining?
8. Why are EBM processes more widely used than LBM?
9. What are cutting fluids and their functions?

Material Science and Metallurgy

1. Draw the Fe-C equilibrium diagram
2. What is meant by fatigue and creep? Draw and explain the creep curve

Strength of Materials

1. What is the significance of a Bending Moment diagram
2. Can Poisson’s ratio be negative?
3. What is Euler’s theory?
4. What is Endurance limit?

Fluid Mechanics and Hydraulic Machines

1. Differentiate between absolute and kinematic viscosity.
2. What is water hammer? What is the function of surge tank and penstock?
3. What is magnus effect? Explain Mach number.
4. What is Cavitation? Explain slip in reciprocating pumps.
5. Describe draft tube and its applications
6. Describe air vessel, hydraulic ram, accumulator and lift
7. Give classification of turbines and the difference between impulse and reaction turbine