Bihar Engineering University, Patna
B.Tech 2nd Semester Examination, 2026
Elements of Mechanical Engineering
Time: 03 HoursCode: 100204Full Marks: 70
Instructions:
- The marks are indicated in the right-hand margin.
- There are NINE questions in this paper.
- Attempt FIVE questions in all.
- Question No. 1 is compulsory.
Q.1 Choose the correct option/answer the following (Any seven question only):[2×7=14]
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Which of the following is not a renewable source of energy?
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Which of the following represents an intensive property
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Which one is the accessory of the boiler?
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Which is not a part of vapour compression refrigeration system?
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Air-conditioning means the control of
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In C.I. engine working on diesel cycle, during the suction stroke
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The Otto cycle is also known as
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Which of the following energy is converted into electricity in a hydro power plant?
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'Tempering' of quenched martensitic steel is necessary to improve the
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The property of a material which enables it to resist penetration or abrasion is called
Q.2 (a) Distinguish between non-renewable and renewable energy resources with suitable example.[7]
(b) What is biomass? How the biomass energy is obtained?[7]
Q.3 (a) Define thermodynamic system and its properties, state and processes. What do you mean by a thermodynamic cycle?[7]
(b) Air initially at a pressure of 75 kPa and temperature of 1000 K and occupying a volume of 0.12 m³ is compressed isothermally until the volume is halved. Subsequently, the volume undergoes further compression at constant pressure till it is halved again. Calculate the work done.[7]
Q.4 (a) Differentiate between internally and externally fired boilers.[4]
(b) Explain the difference between boiler mounting and accessories.[4]
(c) Give the compression between fire tube and water tube boiler. Can a fire tube boiler be used for high pressure steam generation? Explain with reasons.[6]
Q.5 (a) Describe with a neat diagram the essential components of vapour compression refrigeration system.[7]
(b) Sketch and explain a generalized air conditioning system.[7]
Q.6 (a) Explain the working operation of a closed cycle gas turbine with neat sketches. Show all the processes on p-V and T-S diagram.[7]
(b) Differentiate between two stroke and four-stroke engines.[7]
Q.7 (a) Explain with a neat sketch the working principle of nuclear power plant.[7]
(b) Explain with a neat sketch the working principle of thermal power plant.[7]
Q.8 (a) Distinguish between ferrous and non-ferrous metals.[8]
(b) Define the following properties of material (i) Hardness (ii) Strength (iii) Toughness[6]
Q.9 (a) What are the advantages of heat treatments?[7]
(b) Define and explain the heat treatment process, annealing, tempering and quenching?[7]