Solved question paper for EME Dec-2019 (B-TECH 1st-2nd)
Solved Question Paper
Elements of mechanical engineering Dec-2019
PTU • B-TECH • Civil Engineering • 1st-2nd • Dec-2019
elements of mechanical engineering previous year question papers on BRpaper are organized for students of Punjab Technical University’s Bachelor of Technology program, 1st-2nd semester. This section makes it easier to browse subject-wise old question papers for elements of mechanical engineering, so students can review how questions are typically framed in past exams and get a sense of the exam pattern. Many students search for elements of mechanical engineering question bank while preparing for exams, and this page is built to support exactly that kind of subject-wise browsing and revision. BRpaper is not the official website of Punjab Technical University or any institution, and it does not publish official notices or academic updates.
PART-A
1. Basic Concepts of Thermodynamics (08)
Definition of thermodynamic: Need to study thermodynamics; Application areas of thermodynamic; Difference between Microscopic (or, Statistical) thermodynamics and Macroscopic(or, Classical) thermodynamics; Brief concept of continuum; Thermodynamic System : definition, types (Open, Closed and Isolated) and their examples; Thermodynamic System Boundary : definition, types and their examples; Surroundings; Control(fixed) mass and Control Volume concept and their example ; Thermodynamic State; Thermodynamic Property: definition, types citing their examples; condition for any quantity to be a property; State postulate; Thermodynamic equilibrium (which includes Thermal, Mechanical and Chemical equilibrium etc.); Thermodynamic path; Thermodynamic process: definition, concept of reversible process, quasi-static (or, quasi-equilibrium) process, irreversible process, conditions for reversibility and how these are met with, non-flow processes and flow processes, method of representation of reversible and irreversible process on property diagrams; Cyclic process; Thermodynamic Cycle: definition and its concept; Energy and its forms (microscopic and macroscopic); Physical insight to internal energy; Energy transfer across system boundary i.e. transient energies (heat and work); Difference between heat and work; Sign conventions for heat and work interactions; heat and work as path functions; Equality of Temperature and Zeroth law of Thermodynamics.
2. First Law of Thermodynamics and its applications (12)
Definition, essence and corollaries or consequences of first law of Thermodynamics; Expressions for First law of Thermodynamics for a control mass undergoing a Cycle and for process (i.e., a change in state of a control mass) ; Concept of Enthalpy and total energy and differentiation between the two - a thermodynamic property; Compressible and incompressible substances, Specific heats, Difference between Internal Energy and Enthalpy of compressible and incompressible substances; Representation of first law of thermodynamics as rate equation; Analysis of non-flow/ flow process for a control mass undergoing constant volume, constant pressure, constant temperature, adiabatic and polytropic processes; Free Expansion Process and its examples, its representation on Property diagram; Review of concepts of control volume; Expressions of first law of thermodynamics for a control volume (i.e. open system) ; Steady State Steady Flow process and its examples; First law analysis of Steady State Flow process e.g. isochoric, isobaric, isothermal, isentropic and polytropic process; Throttling process and its applications; Flow energy or inertial energy of flowing fluids or, Energy transport by mass; Application of Steady State Flow Energy Equation to various engineering devices.
3. Second Law of Thermodynamics (16)
Limitations of first law of thermodynamics; and how 2nd law is fully able to explain away and thus overcome those shortcomings of Ist law; Thermal Reservoirs, source and sink (Low temperature and high temperatures); Heat Engine, Heat Pump and Refrigerator: definitions, working, efficiency/performance and their real life examples. Justification as to why the actual efficiency of Heat Pump and Refrigerator shall also be ≤ 100% though on the face of it seems to be more than 100%; Various statements of Second Law of Thermodynamics and their equivalence; Philosophy of Carnot cycle and its consequences viz. how each of the individual four processes constituting the cycle contribute in optimizing the output and efficiency of the cycle; Carnot Engine, Carnot Refrigerator and Carnot Heat Pump: definitions, working, efficiency/performance and Limitations of the cycle; Carnot theorem for heat engines, refrigerators and heat pumps; derivation of Carnot efficiency/COP (which seems to be more than 100%); Thermodynamic Temperature Scale; Clausius theorem and Inequality; Philosophy and concept of entropy; Entropy changes during various processes; Temperature - Entropy Chart and representation of various processes on it; Principle of Increase of Entropy; Applications of Entropy Principle; Quality of Energy viz. high and low grade energies; Degradation of Energy; Third Law of Thermodynamics.
PART-B
4. Gas Power Cycles (12)
Introduction; Concept and philosophy of Air Standard Cycle alongwith associated assumptions and advantages; Air Standard Efficiency; Nomenclature of reciprocating piston-cylinder arrangement with basic definitions such as swept volume, clearance volume, compression ratio, mean effective pressure etc; Otto Cycle (or constant volume heat addition cycle), Diesel cycle (or constant pressure heat addition cycle) and Dual cycle (Mixed or Composite or Limited Pressure cycle) with their representation on P-V and T-S charts, their Air-standard (thermal) Efficiencies; Brayton Cycle, Comparison of Otto, Diesel and Dual cycle under some defined similar parametric conditions; Introduction to heat engines; Merits of I.C. Engines and their important applications, Classification and constructional features of I.C. Engines; working of two stroke and four stroke Petrol and Diesel engines and their comparison.
5. Engineering Materials (05)
Materials and Civilization, Materials and Engineering, Classification of Engineering Materials, Mechanical Properties of Materials: elasticity, plasticity, strength, ductility, brittleness, melleability, toughness, resilience, hardness, machinability, formability, weldability. Properties, Composition, and Industrial Applications of materials: metals (ferrous- cast iron, tool steels, stainless steels and non ferrous- Aluminum, brass, bronze ), polymers (natural and synthetic , thermoplastic and thermosetting), ceramics (glass, optical fibre glass, cements), composites ( fibre reinforced, metal matrix), smart materials (piezoelectric, shape memory, thermochromic, photochromic, magnetorheological), Conductors, Semiconductors and insulators, Organic and Inorganic materials. Selection of materials for engineering applications.
6. Centroid, Centre of Gravity and Moment of Inertia: (08)
Difference between centre of gravity and centroid. Determination of position of centroid of plane geometric figures of I, U, H, L, T, C, Circular and Triangular Sections. Centroid of Composite Areas. Determination of position of Centre of Gravity (CG) of regular solids viz. Right Circular Cone, Solid Hemisphere, thin Hollow Hemisphere. Area moment of inertia & mass moment of inertia, Polar moment of inertia, Parallel axes Theorem (or transfer formula), Perpendicular axes Theorem, Radius of gyration, determination of area Moment of Inertia of I, U, H, L, T, C, Circular and Triangular Sections along various axes. Mass moment of Inertia of Circular Ring, Disc, Cylinder, Sphere and Cone about their axis of symmetry and other axes.
Solved Questions
Solved-
What do you understand by intrinsic properties? Give examples.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
Define quasistatic process and list its salient characteristics.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
May 2018 Define a quasistatic process and state its salient characteristics.
-
Dec 2014 Define a quasistatic process and state its salient characteristics.
-
-
Distinguish between point function and a path function.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
May 2013 Distinguish between path function and point function.
-
-
Define thermodynamic equilibrium.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
May 2018 What is meant by thermodynamic equilibrium? How does it differ from thermal equilibrium?
-
Dec 2016 What do you understand by thermodynamic equilibrium?
-
May 2013 Explain the concept of thermodynamic equilibrium.
-
May 2009 Discuss the concept of thermal equilibrium.
-
Dec 2008 What is meant by thermodynamic equilibrium?
-
-
What is throttling process?Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
May 2013 What is the throttling process and give its salient features.
-
May 2010 What is throttling process? Point out its salient aspects.
-
May 2009 What do you understand by throttling process?
-
-
Temperature (increases / decreases / remains constant) during free expansion process.Fill in the Blanks 2 Marks Dec-2019 • PTU B-TECH
-
May 2011 During free expansion process, temperature decreases, increases or remains constant. Select the correct answer.
-
-
Define air standard efficiency.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
May 2020 What is air standard efficiency?
-
Dec 2020 What is Air Standard Efficiency?
-
May 2019 What is an air-standard efficiency?
-
May 2009 What is air standard efficiency?
-
-
Define poisson’s ratio and malleability.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
Enumerate the salient features of magnetorheological materials.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
Differentiate between centroid and centre of gravity.Short Answer 2 Marks Dec-2019 • PTU B-TECH
-
Dec 2016 Define centre of gravity and centroid.
-
-
A figure shows a system comprising of gas in a cylinder at pressure of 689 kPa. Fluid expands from a volume of 0.04 m³ to 0.045 m³ while pressure remains constant. Paddle wheel in the system does a work of 4.88 kJ on the system. Determine the work done by system on the piston.Long Answer Dec-2019 • PTU B-TECH
-
Dec 2019 A figure shows a system comprising of gas in a cylinder at pressure of 689 kPa. Fluid expands from a volume of 0.04 m³ to 0.045 m³ while pressure remains constant. Paddle wheel in the system does a work of 4.88 kJ on the system. Determine the net amount of work done on or by the system.
-
-
A figure shows a system comprising of gas in a cylinder at pressure of 689 kPa. Fluid expands from a volume of 0.04 m³ to 0.045 m³ while pressure remains constant. Paddle wheel in the system does a work of 4.88 kJ on the system. Determine the net amount of work done on or by the system.Long Answer Dec-2019 • PTU B-TECH
-
Dec 2019 A figure shows a system comprising of gas in a cylinder at pressure of 689 kPa. Fluid expands from a volume of 0.04 m³ to 0.045 m³ while pressure remains constant. Paddle wheel in the system does a work of 4.88 kJ on the system. Determine the work done by system on the piston.
-
-
When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: How much will be the heat that flows into the system along path Inm if the work done is 21 kJ?Long Answer Dec-2019 • PTU B-TECH
-
Dec 2019 When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: When the system is returned from m to 1 along the curved path, the work done on the system is 42 kJ. Does the system absorb or liberate heat, and how much of the heat is absorbed or liberated?
-
Dec 2019 When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: If U₁ = 0 and Uₘ = 84 kJ, find the heat absorbed in the processes In and nm.
-
-
When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: When the system is returned from m to 1 along the curved path, the work done on the system is 42 kJ. Does the system absorb or liberate heat, and how much of the heat is absorbed or liberated?Long Answer Dec-2019 • PTU B-TECH
-
Dec 2019 When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: How much will be the heat that flows into the system along path Inm if the work done is 21 kJ?
-
Dec 2019 When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: If U₁ = 0 and Uₘ = 84 kJ, find the heat absorbed in the processes In and nm.
-
-
When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: If U₁ = 0 and Uₘ = 84 kJ, find the heat absorbed in the processes In and nm.Long Answer Dec-2019 • PTU B-TECH
-
Dec 2019 When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: How much will be the heat that flows into the system along path Inm if the work done is 21 kJ?
-
Dec 2019 When a system is taken from state 1 to state m, in Figure 1, along path Iqm, 168 kJ of heat flows into the system, and the system does 64 kJ of work: When the system is returned from m to 1 along the curved path, the work done on the system is 42 kJ. Does the system absorb or liberate heat, and how much of the heat is absorbed or liberated?
-
-
Ina nozzle air at 627°C and twice atmospheric pressure enters with negligible velocity and leaves at a temperature of 27°C, determine velocity of air at exit, assuming no heat loss and nozzle being horizontal. Take Cp = 1.005 kJ/kg.K for air.Long Answer 8 Marks Dec-2019 • PTU B-TECH
-
A reversible heat engine operates between two reservoirs at temperatures 700°C and 50°C. The engine drives a reversible refrigerator which operates between reservoirs at temperatures of 50°C and — 25°C. The heat transfer to the engine is 2500 kJ and the net work output of the combined engine refrigerator plant is 400 kJ. Determine the heat transfer to the refrigerant and the net heat transfer to the reservoir at 50°C.Long Answer 8 Marks Dec-2019 • PTU B-TECH
-
Dec 2011 A reversible heat engine operates between two reservoirs at temperatures of 600ºC and 40ºC. The engine drives a reversible refrigerator, which operates between 40ºC and -20ºC. The heat transfer to the engine is 2000 kJ and the network output from the combined engine and the refrigerator system is 360 kJ. Calculate heat transfer to the refrigerator and net heat transfer to the reservoir at 40ºC.
-
-
The minimum pressure and temperature in an Otto cycle are 100 kPa and 27°C. The amount of heat added to the air per cycle is 1500 kJ/kg. Determine the pressures and temperatures at all points of the air standard Otto cycle.Long Answer Dec-2019 • PTU B-TECH
-
Dec 2019 The minimum pressure and temperature in an Otto cycle are 100 kPa and 27°C. The amount of heat added to the air per cycle is 1500 kJ/kg. Also calculate the specific work and thermal efficiency of the cycle for a compression ratio of 8 : 1. Take for air: cᵥ = 0.72 kJ/kg K, and γ = 1.4.
-
-
The minimum pressure and temperature in an Otto cycle are 100 kPa and 27°C. The amount of heat added to the air per cycle is 1500 kJ/kg. Also calculate the specific work and thermal efficiency of the cycle for a compression ratio of 8 : 1. Take for air: cᵥ = 0.72 kJ/kg K, and γ = 1.4.Long Answer Dec-2019 • PTU B-TECH
-
Dec 2019 The minimum pressure and temperature in an Otto cycle are 100 kPa and 27°C. The amount of heat added to the air per cycle is 1500 kJ/kg. Determine the pressures and temperatures at all points of the air standard Otto cycle.
-
-
Explain the working of two stroke petrol engine giving neat sketch.Long Answer 8 Marks Dec-2019 • PTU B-TECH
-
Dec 2023 Explain the construction and working of four stroke petrol engine.
-
Dec 2018 Explain the working of a two-stroke petrol engine with the help of neat sketches. What are the demerits of two-stroke engines?
-
May 2016 Write short notes on working of two stroke petrol engine.
-
May 2013 Discuss briefly the working of a 4 Stroke Petrol engine.
-
May 2012 Describe the working principle of a two stroke petrol engine with a neat diagram.
-
Dec 2011 Explain the working of two stroke C.I. engine with the help of neat sketches.
-
May 2007 Explain the working of two stroke IC engine with neat sketches.
-
Dec 2007 Explain the working of four stroke IC engine with neat sketches.
-
-
Discuss the properties, salient features, advantages, disadvantages and applications of non ferrous materials.Long Answer 8 Marks Dec-2019 • PTU B-TECH
-
Find the MI of the channel section shown in Figure given below about the X-X and Y-Y axis passing through its centroid.Long Answer 8 Marks Dec-2019 • PTU B-TECH
Explore all data
FAQ
Frequently Asked Questions
Answers about this subject, solved papers, and preparation.
01 Where can I find elements of mechanical engineering previous year question papers for Bachelor of Technology, 1st-2nd semester?
This page lists elements of mechanical engineering question papers uploaded for Punjab Technical University Bachelor of Technology, 1st-2nd semester, organized for subject-wise browsing where available.
02 Are these official Punjab Technical University question papers?
BRpaper is not the official website of Punjab Technical University. These papers are shared for reference and revision purposes only and are not official university material.
03 How can previous year elements of mechanical engineering papers help in exam preparation?
Reviewing past papers can help you understand how questions are typically framed, notice commonly repeated topics, and get a sense of the exam pattern before your own exam.
04 What kind of topics does elements of mechanical engineering usually cover?
The question papers here relate to the official elements of mechanical engineering syllabus set by the university for this course and semester.
05 Does this page include a elements of mechanical engineering question bank or solved answers?
This page focuses on providing access to the previous year question papers themselves. A separate question bank or solved answers may not be available for every paper.
06 Can I find papers for other subjects in the same Bachelor of Technology?
Yes, BRpaper organizes papers by university, course, stream, and semester, so you can browse other subjects within the same Punjab Technical University Bachelor of Technology.