Engineer freshers often face anxiety-inducing interviews, especially their first one. Thus, mastering the Top 20 Interview Questions and Answers tailored for engineering students is crucial. These questions serve as invaluable mock test papers, helping to alleviate interview jitters. However, many students struggle to answer them effectively, leading to nervousness during interviews. 

To address this, we’ve compiled the essential Top 20 Interview Questions and Answers for engineering interviews to aid students in their preparation.

Guide to the Top 20 Interview Questions and Answers for Engineering stream:

Explore the Ultimate Guide to the Top 20 Interview Questions and Answers Catered Specifically for Engineering Students. Dive into various Engineering Disciplines such as:

  1. Civil Engineering
  2. Chemical Engineering
  3. Mechanical Engineering
  4. Electrical Engineering
  5. Computer Science
  6. Electronics & Tele-Communication
  7. Biotechnology

To clarify, these questions are for the Engineering stream. However, if you’re a Polytechnic or Diploma student too, they are relevant for you.

Above all, every Fresher should be original and authentic during interviews. Most importantly, these sample answers will help you get started but do not memorise them.

Civil Engineering

Civil Engineering

1. What gets covered under Civil Engineering?

ACivil Engineering is the design construction and maintenance of artificial environments.

That is to say, it’s an Engineering discipline focused on the construction of dams and structural components. Consequently, it’s applied in construction projects for enterprises like railways, roads and airways.

2. What are the different types of Civil Engineering?

AFor example, these are the various types of Civil Engineering applications in use today:-

  1. Construction Engineering
  2. Coastal Engineering
  3. Civil Engineering Systems
  4. Environmental Engineering
  5. Geotechnical Engineering
  6. Surveying
  7. Water Resources Engineering
  8. Structural Engineering
3. What are some of the software used in Civil Engineering?

AFirstly, AutoCAD and 3D Max are the most popular software used in Civil Engineering. As a result, they get used in reports and billing purposes like construction designs and architectural drawings. Auto-desk 2D and 3D designs are further produced with the help of the two software.

4. What are some of the responsibilities of a Site Manager?

AFor instance, the following activities are usually handled by a Site Manager:

  1. Planning and conceptualizing construction projects
  2. Aiding in decision-making related to projects
  3. Organizing and preparing work schedules
  4. Monitoring health and safety regulations for construction workers
  5. Arranging meetings with clients
  6. Travelling back and forth between sites
  7. Supervising and reporting project progress
5. What are some of the adverse effects of a building collapse?

ADuring a building demolition, severe environmental impact can occur. Therefore, the following effects are rampant in these scenarios:

  • Homelessness
  • Economic loss
  • Property damage
  • Wastage
6. What are the applications of Modulus of Elasticity?

AModulus of Elasticity has several applications like:

  1. Construction of bridges, pillars and beams
  2. Testing deformation property of new materials
  3. Measuring the stress-strain relationship
  4. Calculating, and measuring deformation response under various working loads and weight
7. What is the compressive strength of a fly ash brick?

AThe compressive strength of fly ash bricks is 3.5 N/mm2. In addition to this, a fly ash brick is three times greater than a normal brick made with clay. To clarify, its value is around 10-12N/mm2.

8. What are the different types of roofing systems performed?

AFor example, the following roofing systems are prevalent nowadays: 

  1. Asphalt Shingles
  2. Laminated Asphalt Shingles
  3. Asphalt Roll Roofing
  4. Rubber Membrane Roofing
  5. Cedar Shingles or Shakes
  6. Living Roofs
  7. Solar Tiles
9. What are the different types of slump?

ATo clarify, these are the different types of slumps in use today:

  1. Shear Slump
  2. True Slump
  3. Collapse slump
10. What is the strength of cement and how is it measured?

AThe strength of cement gets tested on hardened cement and mortar cubes. Additionally, they are prepared out of cement with a strength of 53MPa. Further, it’s made of 53-grade OPC Cement and guarantees 28 days of compressive cement strength.

11. What is the crank length and slope of a slab?

AThe smallest length of a crank is 300 mm. Above all, the formula for Crank length is (d1+d2+5) *10 mm. Consequently, here, d1 is the diameter of a smaller bar and d2 is the diameter of the larger bar. Therefore, the slope of a crank is in the ratio of 1:10.

12. How is the unit weight of concrete calculated?

ATo get the unit weight of concrete, follow the formula given below:

Multiply the length, height and width of the area where the concrete gets filled. Further, calculate the concrete volume and multiply it by 3. Additionally, convert it into cubic feet using the formula: 143.38 pounds/feet^3.

13. What is the process for hiding dimensions in AutoCAD?

AFor instance, the process to hide dimensions in Auto-CAD is:

  1. Right-click the dimension on the drawing sheet
  2. Select Edit from the menu
  3. The dimension value gets represented by <<>> in the Edit Dimension dialog box
  4. Click on the Hide Dimension Value checkbox. After that, enter the dimension of the string displayed
  5. Close the dialogue box by applying changes and click OK
  6. The text entered in the string now replaces the dimension value.
14. What does segregation bleeding mean?

AIn Civil Engineering, Bleeding is a process and state of mixing water in the concrete. Therefore, because of this, the concrete rises above the material surface.

15. What is the unit weight of Steel?

APer cubic meter, the unit weight of steel is 7850 kegs. Moreover, it depends on the exact composition of the steel as an alloy of carbon and iron.

16. Who was the Father of Modern Civil Engineering?

AJohn Smeaton was the first person who referred to himself as a Civil engineer back in the 18th century. After that day, he was later recognised as the Father of Civil Engineering.

17. What is OSHA standard compliance?

AOSHA stands for Occupational Safety and Health Act.

Above all, it’s designed to fulfil the health and safety needs of construction workers. In addition to this, it is a health and safety standard followed by many industrial segments. Moreover, multiple corporate offices engaged in construction projects also follow this Act.

18. What is the Release of Lien?

ARelease of Lien is a written document executed by an individual or firm supplying labour. Consequently, it refers to a service contract on a project that releases liens against properties.

19. What are some of your strengths and weaknesses?

AMention your core strengths on your resume. Recruiters don’t have to ask you for cross-verification later. However, avoid beginning the answer by talking about your weaknesses first.

Moreover, highlight your best-selling strengths. Do not explain weaknesses that might deter you as a Civil Engineer.

Additionally, speak about how you plan to improve on those weaknesses soon.

20. Why do you want to work at our facility?

AFor example, A good yet polite answer to this question can be:

Sir/ Ma’am, as a fresher I want to build my career by working at your reputed facility. Further, I believe that I will get a platform to prove myself and utilise my knowledge and skills. So, I want to acquire practical training by working directly at sites in your facility.”

Chemical Engineering

Chemical Engineering

1. What does Entropy mean?

AEntropy is a measure of disorder within an existing system. Additionally, it describes the behaviour of substances within an equilibrium environment. Moreover, gases inherently have greater entropy than liquids.

2. What is an Isochoric process?

AIt is a thermodynamic process in which a system has a constant volume. Further, since the volume is constant the system will have no work. Therefore, it determines the relationship between pressure and temperature within the system.

3. What are some of the advantages and disadvantages of a PFR?

APFR has the highest conversion rates among all the reactor types. As a result, it controls various system reactions and operating conditions. Likewise, they work similarly on principles such as FBCR. Despite this, PFRs however are costly with high operational and maintenance costs.

4. What is Carbon Sequestration?

ACarbon Dioxide removal is a long-term removal or capture of carbon dioxide. Moreover, the capture slows down atmospheric CO2 pollution. It also aids further in the mitigation of global warming.

5. How does a Spray Condenser work?

AA Spray Condenser coolant gets sprayed using nozzles. In other words, this appliance gets poured into vessels and supplied with vapour.

Consequently, the spray nozzle and vessels produce a fine spray of liquid. It also gives further a larger area for heat transfer and time for liquid droplets to condense.

6. What is the principle of pneumatic conveying?

AThe principle of pneumatic conveying states that bulk goods can move through air. The flowing air further transmits a propulsion force through the conveying line.

Therefore, it requires a pressure difference from the beginning and end of the pipeline. So, to overcome this difference conveying blowers and compressors are being utilised.

7. How does catalytic converters work?

ACatalytic Converters change harmful substances in car exhaust gases. For instance, it filters gases like Carbon Monoxide, Nitrogen Dioxide and Hydrocarbons. Further, it changes into less harmful substances like Carbon Dioxide and water vapour.

8. How do chemical paints dry?

AIn the case of paints, a pigment is a tiny particle suspended in the solvent-binding medium. That is to say, when the paint dries, the solvent mixture evaporates.

Therefore, it leaves the pigment suspended in the binding medium in the harder layer.  These evaporating solvents are further largely responsible for the smell of the paint used.

9. What is Quicklime?

ACalcium Oxide (CaO) also known as Quicklime or Burnt Lime is a widely used chemical compound. Moreover, it is a white, caustic, alkaline, crystalline solid at room temperature.

10. What procedure is used for extracting hydrogen from water?

AElectrolysis uses electricity to split water into hydrogen and oxygen atoms. Moreover, this reaction takes place in a closed unit called an Electrolyzer.

11. What are food additives and why are they used?

AFood additives are substances added to enhance the taste and calorific value of food. Moreover, they may be natural, nature-identical or artificial.

12. What compounds are responsible for foul smells in wastewater plants?

ACertainly, odour in the wastewater treatment plant happens because of  a variety of compounds like:

  • Reduced Sulphur compounds like Hydrogen Sulphide, mercaptans, organic sulphides
  • Nitrogen compounds e.g. Ammonia, Amines
  • Volatile fatty acids such as Formic Acid, Butyric Acid
  • Aldehydes and Ketones.
13. What are some of the characteristics of a good quality water cooling tower?

AA good quality cooling tower operates on a pH level around neutral since water is the carrier fluid. Impurities such as Sulphur and Chlorine hinder the performance of heat transfer.

Therefore, it gets filtered at locations with low air humidity and high temperatures. Further, it allows the moisture to evaporate effectively. Additionally, the process is characterised by the wet-bulb temperature of materials.

14. How can gas flow be estimated based on two pressure measurements?

ATo find the velocity of fluid flow, the pressure gets determined at two reference points. After that, the differential pressure must be multiplied by two and divided by the density of the gas.

15. What problems occur with large temperature differences in boilers?

AWhen a boiler overheats several issues may arise, most noticeably leaking. The conduction of heat further results in expansion. As a result, it changes into a solid causing structural issues.

16. What Is a Heat Exchanger and what are some of the advancements in Heat Transfer?

AA Heat Exchanger is a heat transfer system. It maximises heat transfer between two or more fluids or gases. Additionally, they are used for both cooling and heating purposes.

For instance, one major recent advancement is the use of cross-flow heat exchangers. Moreover, it uses heat exchanger tubes to transfer heat between fluids near one another.

17. What is the major difference Between Extractive and Azeotropic Distillation?

AThe major difference between Extractive Distillation and Azeotropic Distillation involves azeotrope formation.

To clarify, Extractive Distillation is a process where azeotrope formation separates the compound components. However, a second azeotrope is necessary to break up the components further.

18. What is the concept of Thermodynamics?

AThermodynamics is a specialised branch of physics. As a result, it studies heat, pressure and object volumes.

Moreover, it’s concerned with the interactions among heat, work, temperature and energy distribution. Further, it studies substances and how changes affect each other.

19. What are some of the models or methods employed for meeting deadlines?

AThis HR Interview question tests the Time Management skills of candidates. Further, it helps employers know how to schedule projects and meet target deadlines. Moreover, back it up with realistic examples of how you’ve done this earlier. Additionally, tell me how you will organise yourself.

For example, by adding reminders, tasks and notepads. In other words, it will allow me to structure my tasks and optimise efficiency.

20. How will you troubleshoot and identify faults while communicating findings?

AThis question measures a candidate’s problem-solving ability. Consequently, Troubleshooting is an important skill for a Chemical Engineer. As a result, deliver your response and focus on how you solved problems. Additionally, communicate any struggles or failures you experienced.

Mechanical Engineering

Mechanical Engineering

1. What is the fundamental difference between Scavenging and Supercharging?

AIt is the process of flushing out burnt gases from engine cylinders by introducing fresh air into it. Moreover, this is usually done before the exhaust stroke ends. Supercharging, on the other hand, is the supply of compressed atmospheric air.

2. Under what conditions is the work done in a reciprocating compressor is least?

AFor example, it is least when the compression process approaches isothermal equilibrium. Therefore, an attempt is being made to cool the air during compression itself.

3. What is the difference between Stalling and Surging in rotary compressions?

AStalling is a local phenomenon and it occurs when airflow breaks away from the blades. Likewise, surging causes a complete breakdown of airflow and it affects the entire machine.

4. Why is the electric motor of a fan with backward-curved blades never overloaded?

AThe maximum power consumed is about 70% of the maximum flow in the case of fans with backward blades. Consequently, for this higher flow, the power consumption gets lower and is never overloaded.

5. What is pitting and how is it caused?

APitting is the non-uniform corrosion on metal surfaces occurring in small pits. Further, it’s caused by a lack of uniformity in metal surfaces.

6. What does Caustic Embrittlement infer?

ACaustic Embrittlement is a physical change in metals that makes them brittle and cracked. Subsequently, it occurs particularly in seams of riveted joints and around rivet holes.

7.  How does one prevent safety valves from sticking to seats?

AA Safety valve gets blown off periodically so that no corrosion can take place. On the other hand, it’s done on the valve surface and the valve seat is fully protected this way.

8. Why are manholes in vessels usually elliptical in shape?

A: Elliptical shapes have minimum areas of opening. Therefore, the plates weaken the least. Further, it is convenient to insert and take out the cover plate from elliptical openings.

9. Why do boilers get purged every time before starting a fuel fire?

APurging ensures that any unburnt fuel in the boiler furnace gets removed. Above all, it’s done so that it doesn’t lead to a possible explosion.

10. What is the critical temperature of refrigerants?

A: Critical temperature is the maximum temperature of a refrigerant. Later, it condenses into liquid form. After that, it remains as gas irrespective of the pressure applied.

11. What is the principle of Mechanical Refrigeration?

A: Under the principle of Mechanical Refrigeration, a volatile liquid will start boiling. Most importantly, under proper conditions, it will absorb heat from nearby surrounding objects.

12. Why high latent heat of vaporisation is desirable in refrigerants?

A: A high latent heat of vaporisation results in a small amount of refrigerant. Further, a lesser circulation system of refrigerant for the same tonnage.

13. What is the function of a Thermostat in the cooling system of an engine?

A: A Thermostat ensures optimum cooling of the engine. Consequently, it contributes to excessive cooling that decreases the overall efficiency. Meanwhile, it allows cool water to go to the radiator beyond a predetermined temperature.

14. Why a gas turbine power plant needs an efficient compressor?

A: A Gas Turbine Power Plant needs an efficient compressor. Therefore, a large portion of the turbine operation gets eaten away by the compressor. Moreover, its inefficiency affects the net power output and cost of power generation.

15. What is the advantage of a fast breeder reactor?

A: A fast breeder reactor has rapid self-breeding of fossil fuel in reactor operations. It further offers about sixty times the output with similar natural uranium resources. Therefore, it’s preferred over ordinary non-breeder nuclear reactors.

16. What is the purpose of using biological shields in nuclear plants?

A: Biological Shields of heavy concrete prevent exposure to neutrons. It further prevents beta rays and gamma rays that are hazardous to living organisms.

17. What is the difference between nuclear fission and fission chain reactions?

A: Nuclear Fission is the nucleus splitting into two equal fragments by heat release. Moreover, Fission chain reactions are self-sustained sequences of fission reactions in a controlled setting.

18. What is Heavy Water and what is its use in nuclear plants?

A: Water containing heavy isotopes of hydrogen (Deuterium) is Heavy Water.

As a result, Heavy Water as a moderator, has low cross-section absorption of neutrons. It further slows down fast neutrons and moderates chain reactions compared to ordinary water.

19. Why should we select you and what are your plans as a Mechanical Engineer?

A: An HR Recruiter tests your personality and your mannerisms with this question. Subsequently, they aim to enquire about your goals and verify whether you are stable and independent. Certainly, they might negotiate your expectations and bring you down.

However, one should relax while speaking to the HR Manager/ Recruiter. Moreover, it signals confidence and determination for finalising you as a candidate.

20. What are some of your strengths and weaknesses?

A: Even if you have mentioned your core strengths, an HR Recruiter may cross-verify them. So, do not begin the answer to this question by talking about your weakness first.

On the other hand, highlight your best-selling strengths and explain a weakness that’s not related. Meanwhile, try to speak about how you plan to improve on your weakness soon.

Electrical Engineering

Electrical Engineering

1. What does Electrical Engineering mean to you?

A: Electrical Engineering is the installation and application of electronics, electricity and electromagnetism. It also further deals with voltage regulation. Moreover, particularly AC above series of 110 or 220V.

2. What is Electric Traction and its applications?

A: Electric Traction is the power for an entire grip power of electric current in the power grid system. Therefore, it’s utilised for electricity conversion purposes by railways, trams and trolleys. To clarify, for instance, DC motors are used for electric traction systems.

3. What is an RLC circuit and its purpose?

A: An RLC circuit is an electrical circuit consisting of a resistor (R) and an inductor (L). Sometimes, it also contains a capacitor (C) linked in a parallel connection. Therefore, it is also known as a second-order circuit. Consequently, any current is directly obtained by a next-order discrepancy equation.

4. What is an Automatic Voltage Regulator?

A: An Automatic Voltage Regulator is a central part of Synchronous Generators. It controls the production voltage of the originator by controlling its excitation current. Further, it directs the reactive productivity power of a Generator.

5. What are the different types of semiconductors?

A: There are two kinds of semiconductors: Intrinsic semiconductors and Extrinsic semiconductors. Intrinsic semiconductors contain no significant dopant species. Extrinsic semiconductors on the other hand contain N-type semiconductors and P-type semiconductors.

6. What is a Unilateral and Bilateral Circuit?

A: A Unilateral Circuit is a circuit which alters with the present voltage flow. Moreover, Bilateral Circuits do not change the existing direction or voltage change.

7. What is normally meant by the maximum power transfer theorem?

A: It mentions the state for maximum power transmission from source to load. On the other hand, in a bilateral network, the utmost power gets transferred. Besides, it happens from the base source to the load when the outside load resistance equals. Thus, the interior resistance of the source of the circuit remains unaffected.

8. What is the Marx Circuit?

A: A Marx Circuit is used in generators. It happens for charging several capacitors in parallel and discharging series connections. Therefore, the voltage required for testing remains higher than the power source present.

9. What is an Ideal Transformer?

A: An Ideal Transformer is an imaginary transformer in which no losses occur at all. In other words, the transformer’s input power is equal to the output power of the transformer.

For instance, i.e. it refers to a 100% efficiency and is just a theoretical transformer. Therefore, there must be some losses in a real transformer.

Lastly, it is represented in this formula:

Transformer Input Power = Transformer Output Power.

10. What are some of the limitations of Ohm’s Law?

A: Ohm Law does not apply to a unilateral circuit or a non-linear circuit. The criterion for Ohm’s law is that the resistance must be constant and it depends on the temperature. Therefore, the resistance of a non-linear or unilateral circuit varies with voltage & current. Moreover, it is not applicable in such a circuit.

11. What is a Motor Starter?

A: A Motor Starter is a device that is usually connected in series. This motor decreases the starting current and increases the current. During this process, it is initially started and then stopped for overload protection.

12. What is a Magnetic Starter?

A: A Magnetic Starter is a device designed to provide a safe starting method for electric motors. Additionally, with heavy loads, it includes a contactor as an essential component. Therefore, this kind of motor provides power-cutoff, under-voltage, and overload protection.

13. What is the difference between a Generator and an Alternator?

A: A Generator and an Alternator both convert mechanical energy into electrical energy. The key differences between them are:

A Generator has a stationary magnetic field and the armature rotates inside it. On the other hand, in an Alternator, the field rotates inside a conductor winding stator.

14. What is Reverse Polarity and how does it get fixed?

A: An electrical outlet has three wires, neutral & hot and live wire. In Reverse polarity, the neutral wire gets connected to the hot wire. Further, it can create shock hazards because the ON/OFF switch cuts off. So, only the neutral wire from an appliance gets plugged into the outlet. However, it is usually fixed by swapping wires.

15. What is a Zener Diode?

A: It is a special type of diode that conducts current forward and also in reverse. Moreover, the polarity change occurs once the Zener voltage is attained. So, it’s used to maintain a constant voltage over a range of currents. Additionally, it serves as a safety device or a voltage regulator. Therefore, it is helpful and protects electrical components from excess voltage.

16. What is a Vacuum Circuit Breaker?

A: A Circuit Breaker breaks the circuit by opening the contact terminals. It achieves this by generating an arc between terminals. After that, the arc gets quenched using various mediums. In a Vacuum Circuit Breaker, the medium for arc quenching is a vacuum. Vacuum has a high voltage arc quenching ability as compared to air. So, it’s used in high-voltage circuits.

17. What is a Reverse Power Relay?

A: A Reverse Power protection Relay is a directional protection device. This device prevents a Generator from taking current back from the grid. In addition to that, it produces a motoring effect and prevents damage to the generator.

18. What kinds of cables are normally used for power transmission?

A: Four kinds of cables are primarily used for power transmission:

  1. Long-distance cables
  2. High-tension cables
  3. Super-tension cables
  4. Low-tension cables

Long-distance cables like power lines get classified as per their size and capacity. Low-tension cable transmits voltage up to 1,000 volts or one kilovolt (1 kV). High-tension cables transmit between 1 kV and 23,000 volts (23 kV). Super-tension cables carry between 66,000 volts (66 kV) and 132,000 volts (132 kV).

19. Why should we select you and what are your plans as an Electrical Engineer?

A: An HR Recruiter tests your personality and your mannerisms through this question. Their main aim is to enquire about your goals and verify whether you are stable and independent. They might negotiate your expectations and try to bring you down. So, speak to the HR Manager/ Recruiter expressing confidence and determination in yourself.

20. How will you troubleshoot and identify faults while communicating findings?

A: This question measures a candidate’s problem-solving ability. Troubleshooting is an important skill for an Electrical Engineer. Be cautious with your response. Focus on how you solved problems and communicate any failures you experienced.

Computer Science

Computer Science Engineering

1. What is a Superclass attribute?

A: A Super Class is the basis of all classes. The object of the rest of the class has all the characteristics related to the Superclass.

2. What do you mean by SDLC?

A: SDLC stands for ‘Software Development Life Cycle’ policy. It is a process of producing quality software products in less time. Further, it optimises various stages involved like:

  • Software Planning
  • Designing Software
  • Software construction
  • Testing of Software
  • Software deployment.
3. What is an Integrated Development Environment?

A: Integrated Development Environment (IDE) is a GUI-based software program. It’s designed to help Programmers build applications. It has the necessary software programs and software library packages to assist them further.

4. What is Artificial Intelligence (AI) in today’s day?

A: Artificial Intelligence or Machine Intelligence is a jargon in the IT industry. This has been necessary to build smart machines capable of performing intelligent tasks. The main aim of AI is to solve problems in faster and more convenient ways.

5. What is Machine Learning?

A: Machine Learning (ML) is an intelligent application of Computer Science Engineering. This allows systems to learn from predefined examples. Further, the algorithm can continuously improve without being explicitly coded by Programmers.

6. What is Deep Learning technology?

A: Deep Learning is computer software that mimics the network of neurons in the human brain. It is a subset of Machine Learning (ML), so because it makes use of deep neural networks.

7. What is a Byte Stream in Computer Science?

A: Byte Stream performs input and output tasks on Unicode text composed of 8 bits.

8. What is the Primary Memory or RAM?

A: Primary Memory or RAM is the main memory of a computer. Certainly, this is what the Central Processing Unit (CPU) uses to fetch resources. It stores temporary volatile information until the information-fetching process finishes its execution.

9. What is Cryptography?

A: Cryptography is a technique for concealing the real meaning of certain information. It further transforms encoded information into discreet formats. Therefore, this data is very hard to interpret by humans or binary systems.

10. What Is an Object Class in C++?

A: An Object is a package that contains related data and instructions. The data relates to what the object represents. On the other hand, the instructions define how an object relates to other objects and itself.

11. What is Inheritance class?

A: Inheritance is a property that a Superclass uses to pass its characteristics to a subclass. Moreover, a Subclass has the option of modifying these characteristics. Further, it makes a different but fundamentally related class from the super-class.

12. What is a Computer System?

A: A Computer System is a combination of CPU, memory and Operating System (OS). Further, it has peripheral devices connected to it such as a keyboard, mouse, speakers, etc.

13. What are Algorithms and their uses?

A: An Algorithm refers to a definite sequence of executable and well-defined instructions. It trains systems for solving a class of problems or performing computation sequences.

14. What are some of the types of Access Modifiers?

A: There are four kinds of access modifiers: Default, Private, Public and Protected. The Private Modifier makes the class or method visible to a specific class. On the other hand, the Public Modifier makes it visible to everything. The Protected Modifier however makes it visible only to particular packages.

15. What is a Constructor?

A: A Constructor is a method or method used when creating object classes. Parameterized and default constructors are the two different kinds of constructors used.

16. What is a File?

A: A File is a basic component of a storage location that stores information and data. Files are always stored inside storage devices using file names. Files maintain data and information permanently unless deleted.

17. What is the basis of the OSI Model?

A: The OSI Model is an orientation replica of how applications converse over networks. It consists of seven layers:

  1. Physical
  2. Presentation
  3. Application
  4. Session
  5. Transfer
  6. Network
  7. Data Link Layer
18. What is a Singleton Class?

A: A Singleton Class confines the number of objects shaped for a class to one. Moreover, it gives the suppleness of creating more objects if circumstances change.

19. How will you troubleshoot software issues and identify faults in application deployments?

A: This question measures a candidate’s problem-solving ability. Troubleshooting is an important skill for a Computer Science Engineer. Demonstrate your technical acumen and focus on how you solved problems earlier.

For instance, hardware and software issues. Further, you can communicate any struggles or failures you experienced.

20. Why do you want to join our company?

A: This is one of the most critical questions asked by HR Recruiters. You should research the company in advance before answering this question.

For instance, by browsing their websites and social media handles. Certainly, it will acquaint you with knowledge about workplace culture and prospects. Meanwhile, talk about the achievements of the company or the work environments offered. Try to relate to the positive aspects of the company. In addition to this, you can speak about your motivation to join them further.

Electronics & Tele-Communication

Electrical Engineering

1. Which equipment is needed for a VOIP call?

A: A Voice-Over-Internet-Protocol call requires the following specific technical equipment:

  • A Broadband connection
  • VOIP-supported smartphones
  • Nexton Soft Switches
  • A Router
  • An Audio codec
  • Astric Server
  • Dial-up internet connection.
2. What is the Protocol Testing standard and what are the tools used?

A: Protocol Testing is the testing of node functionality for standard message flow. It gets monitored for compliance and a Tester sends the standard message to the node tested.

Additionally, the testing tools used are:

  1. Glomosim Simulator: To test 100 nodes on a single CPU
  2. Abacus5000: To test the SIP
  3. Etherpeek: To test IP
  4. Nethawk – for SS7 testing
  5. Wireshark – for SS7/IP testing
  6. K1297- for testing G20 (Tektronics)
3. What is SS7?

A: SS7 is a global standard for Telecommunication channel signalling. It defines various procedures and protocols for the Public Switch Telephone Network. The SS7 standard therefore aids in information exchange over digital signaling networks.

Additionally, some of the main functions of SS7 are:

  1. Providing call control and remote network management
  2. Controlled message exchange for SS7 telephone exchanges
  3. Transforming information from Signaling Points
  4. SS7 Signaling Transfer Points.
4. What is a Broadband internet connection?

A: Broadband is internet access with high speed. However, unlike dial-up connections, broadband connections are permanently connected. Further, internet and telephone calls can take place simultaneously without a landline. Therefore, Modulation of Broadband signals is necessary to transform data better.

5. What is the meaning of Asynchronous Transmission?

A: Asynchronous Transmission uses start and stop bits signifying the ASCII characters transmitted.

For instance, ‘0100 0001 would become ‘1 0100 0001 000 1 0’’. There is an additional one bit at the beginning and end of the transmission.

Further, it refers to the receiver that a character got entered or a character deleted. Moreover, it’s used when data needs to be sent intermittently. As a result, the receiver recognizes the second packet of the information sent.

6. What is Telecommunication Bridging?

A: Telecommunication Bridging is an advanced technique used in packet-switch networks. It does not assume the address location of networks. The device address and location get recorded in a MAC address table for broadcasting. Moreover, it refers to transparent bridging that predominates in Ethernet connections. Further, source-route bridging is used for token ring networks.

7. What do you know about MTU?

A: Maximum Transmission Unit (MTU) is the largest packet size passed via protocols. This usually occurs for a given layer. Communication interfaces such as NIC and serial ports are associated with MTU parameters. Moreover, it’s a fixed unit as per Ethernet recommended standards. Further, high bandwidth efficiency accompanies a higher MTU.

8. What is the difference between GSM and CDMA?

A: The Global System for Mobiles (GSM) uses multiple frequencies. It requires TDMA and FDMA for accessing signals with a voice rate of 9.6 KBPS. However, less bandwidth with Code Division Multiple Access (CDMA) has a frequency carrier. It uses Phased Locked Loops for better power control. Moreover, it has a voice rate of 14.4 KBPS and follows soft handoff for efficient call handling.

9. What is the functionality of TCSM?

A: TCSM is an acronym for Transcoder/ Sub-Multiplexer. Some of its main functions are:

  • Carrying Interface traffic through radio frequency by air
  • Compressing the data for efficient transmission (from 64 KBPS on the interface side to 13 KBPS on air.
10. What are some of the reasons for a call drop?

A: A Call Drop occurs for the following reasons:

  • Slips occurring in media
  • Antenna tilting issues
  • Out-of-range phone service
  • Electrical and Mechanical tilts
  • Signal interference.
11. What is the Simple Network Management Protocol?

A: Simple Network Management Protocol (SNMP) is a UDP-based network protocol suite. SNMP was first invented and designed further by the Internet Engineering Task Force. SNMP has an application layer database schema and a group of data objects.

Some common messages communicated between the SNMP Manager and the SNMP Agent include:

  • SET
  • GET
  • TRAP

Its primary concern is to monitor network-attached devices for various administrative requirements.

12. What is the TTCN-3?

A: Testing and Test Control Notation Version 3 (TTCN-3) is a typed test scripting language. It’s used for testing communication systems conformance and specifies test infrastructure interfaces. It was later implemented further under concrete communication environments with standardised adapter interfaces.

13. What are the different types of communications possible?

A: There are two different types of communication possible: Analog and Digital communication.

Analog Communication takes audio or video signals and turns them into electronic pulses. Digital Communication Technology breaks the signal into binary formats. Here, the audio or video data gets represented by a series of “1”s and “0”s.

When compared with Analog Signals, Digital Signals ensure the quality of transmission. Moreover, they further use high-precision components for less power consumption.

14. What is the meaning of a Sampling Theorem?

A: The Sampling Theorem takes samples of continuous signal outputs. Hence, the sampling rate is equal to or greater than twice the cut-off frequency. Therefore, the minimum sampling rate is known as the Nyquist rate.

15. What is commonly known as RF?

A: Radio Frequency (RF) is a frequency rate of oscillation within the range of about 3 Hz to 300 GHz. This range corresponds to the AC electrical signal frequency produced in radio waves. In other words, most of this range is beyond the vibration rate that most mechanical systems. It further responds to RF oscillations in electrical circuits or electromagnetic radiation.

16. What is the meaning of AM and FM and where are they used?

A: AM: Amplitude Modulation is where the amplitude of the carrier varies with the signal.

FM: Frequency modulation is where the frequency of the carrier does not vary with the signal.

AM in video signals like TV sets ranges from 535 to 1705 kHz. On the other hand, FM in audio signals in radio receivers with ranges between 88 to 108 MHz

17. What is a Repeater?

A: A Repeater is an electronic device that receives a signal and retransmits it at a higher level. Similarly, it can also do it for higher power on the other side of the obstruction. So, the signal can cover longer distances without degradation.

18. What is Multiplexing?

A: Multiplexing or Muxing is a process where many analogue message signals get combined into one signal over a shared medium. The aim is to share an expensive resource.

For example, in telecommunications, several phone calls get transferred often using one wire.

19. Why do you want to join our company?

A: This is one of the most critical questions asked by HR Recruiters. You should research the company in advance before answering this question.

For instance, by browsing their websites and social media handles. Certainly, it will acquaint you with knowledge about workplace culture and prospects. Meanwhile, talk about the achievements of the company or the work environments offered. Try to relate to the positive aspects of the company. In addition to this, you can speak about your motivation to join them further.

20. What do you think constitutes an ideal work environment?

A: The intention is to understand if a candidate can fit into the company’s work environment. Employers want to ensure that employees are productive and satisfied. So that they can do their work while retaining them, in the long run, to analyse if they can adapt to their culture.

Biotechnology Engineering

Biotechnology Engineering

1. What are the domains under Biotechnology Engineering?

A: Bio-technology is a domain where a team of scientists research and work together. Moreover, scientific methods help to enhance the nutrition level and food taste. Bio-Technology Engineering uses fewer pesticides and improves crop harvests.

2. What does GMO mean and what importance does it have in the Biotechnology field?

A: GMO means Genetically Modified Organism. Here, two different genetic molecules are further combined into one new genetic organism. Moreover, it’s usually done by using Genetic Engineering techniques.

3. What is DNA and who discovered its structure?

A: DNA or Deoxyribonucleic Acid is the genetic material for most living organisms, however, except for some viruses such as AIDS where RNA is the genetic material.

A DNA molecule is a long-chain polymer made of monomeric units called nucleotides. A nucleotide has a deoxyribose sugar molecule, phosphoric acid group and nitrogen base. DNA and RNA belong to a category of macromolecules known as nucleic acids.

The structure of DNA was first proposed by Watson and Crick in 1953.

4. What does the term Restriction Enzyme Digestion of DNA mean?

A: Restriction Enzyme Digestion DNAs or Endonucleases are bacterial enzymes. They bind and cleave DNA at specific target sequences. They further consist of a short palindromic sequence and cleave within DNA sites.

5. What is the role of Agarose Gel Electrophoresis in RNA?

A: Formaldehyde Agarose Gels allow separation and identification of RNA molecules on migration. Unlike DNA, RNA has a high degree of secondary structure making it necessary to use a denaturing gel.

Formaldehyde Agarose Gel disrupts the secondary structure. So, RNA molecules get separated during charge migration by molecule size.

6. What is 2D Gel Electrophoresis (2D PAGE)?

A: 2D Gel Electrophoresis (2D PAGE) is a method of protein separation. Here, the proteins in the mixture separate first. It changes according to their isoelectric point (pI) or isoelectric focusing (IEF).

Further, it’s based on molecular weight in sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The 2D PAGE is for isolation, separation and purification of proteins. It also assists in further characterization with mass spectrometry.

Hence, the identification of specific proteins or isoforms gets isolated with 2D PAGE.

7. What are the different types of Bio-Technology available?

A: The different types of Biotechnology are:

  1. Red Biotechnology
  2. White Biotechnology
  3. Green Bio-Technology

Red Biotechnology in medical devices like antibiotics. Green Biotechnology aids the agricultural process to grow environmentally friendly crops. White Biotechnology is instead used in industrial processes like chemical reactions.

8. What is Bioethics in Biotechnology Engineering?

A: Bio-ethics is the combination and analysis of social, political and environmental consequences. It inspects the implications of Bio-Technology applications and biomedical products.

9. What is a Living Modified Organism (LMO)?

A: Living Modified Organism (LMO) is an application of modern Biotechnology. It refers to a living organism containing genetic materials. It could be sterile, injections or viruses.

10. What are the problems faced by using genetic engineering tools?

A: Genetic engineering tools expose all plants and crops to pesticides and herbicides. However, they are often overused to maintain crop freshness and retain food taste. Traditionally farmers avoid using pesticides for crops but nowadays they use them liberally.

11. How are Fungal Genomic DNA isolated?

AFungal Genomic DNA gets isolated from a culture disc or liquid culture. It’s done by harvesting mycelium directly. Centrifugation and supernatant further remove the DNA before isolation or storage.

After that, the liquid culture cells get pelleted. At a temperature of 80-degree Celsius harvested samples are often frozen or freeze-dried.

12. What does the term DNA Recombination infer?

A: There are DNA segments that do not interact with the DNA helix. It also lets chromosomes in human cells occupy isolated areas in the nucleus. called chromosome territories.

As a stable information repository, the physical isolation of various chromosomes is significant. It further tries to communicate during chromosomal crossover for recombination. However, when two DNA helices break, chromosomal crossovers lastly recombine as DNA.

13. What is Clonal Energy?

A: Clonal Energy is a state in which the antigen cannot activate the cells of an organism.

14. What is Bio-Media and its application?

A: Bio-media is a concept to describe the informatic reframing of biological components. It also relates to methods and processes. It aids in identifying biological research areas through a scientific lens.

15. What is a Secreted Immunoglobulin?

A: Secreted Immunoglobulin is a form of antibody secreted by cells of B lineage.

16. What is a Thymocyte in the Biotechnology field?

A: A Thymocyte is a developing T cell present in the thymus in the human body.

17. What is an Interferon-Induced Antiviral state?

A: Interferon reacts with interferon receptors of cells. It causes a cell to enter a state called an Interferon Induced Antiviral state.

18. How harmful is the solution Phenoxyethanol?

A: Phenoxyethanol is harmful and gets absorbed through the skin. However, with little toxic effects, it doesn’t affect humans as much as animals. Phenoxyethanol is used in cosmetics as a bactericide that kills bacteria.

19. What are the challenges of Bio-Technology Engineering and how will you overcome them?

A: A Recruiter analyses your understanding of Biotechnology Engineering through this question so, if you’re well-versed in the industry reply as per your understanding.

For instance, you can say something like:

The future of Bio-Technology is constantly changing. Companies need to adapt to the changing conditions and research on new products. Moreover, it helps them remain viable amidst competition.”

You can show your inclination further by saying how you will research new products. Additionally, you can explain the scientific methods you will use for this purpose.

20. What are the possible dangers associated with Biotechnology Engineering?

A: Applicants should be well-versed in answering this tricky question. You can say that Biotechnology Engineering has its advantages and disadvantages.

Certainly, you can mention how it’s constantly adapting to such changes. However, when you’re talking about risks, mention scientific advancements and risk management steps.


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