Basic Mechanical Engineering (BME) - Dec 2015
First Year Engg (Semester 2)
TOTAL MARKS: 50
TOTAL TIME: 2 HOURS (1) Solve Q.1 or Q.2, Q.3 or Q.4, Q.5 or Q.6, Q.7 or Q.8
(2) Assume suitable data, if necessary.
Solve any one question from Q1 and Q2
1 (a) Explain the following machine elements:
i) Axle and shaft
ii) Parallel key
iii) V belt drive.(6 marks) 1 (b) Define mechanism, machine and state their examples. Explain the mechanism used in single, stage, single acting, reciprocating air compressor with neat sketch.(6 marks) 2 (a) Explain working of disc brake with schematic (simple) sketch.(4 marks) 2 (b) Explain any four mechanical properties of engineering material.(4 marks) 2 (c) How are engineering materials classified? Write a short note on plain carbon steel.(4 marks)
Solve any one question from Q3 and Q4
3 (a) Explain hot forging process with neat sketch.(4 marks) 3 (b) Draw a labelled block diagram of lathe machine.(4 marks) 3 (c) Identify and explain suitable manufacturing process to impart smooth surface finish and dimensional accuracy to piston pins, balls and rollers of rolling contact bearing etc.(4 marks) 4 (a) Draw self-explanatory sketches of various sheet metal forming processes.(4 marks) 4 (b) Identify and explain suitable manufacturing process to join two mild steel plates.(4 marks) 4 (c) Explain drilling operation performed on lathe machine and radial drilling machine.(4 marks)
Solve any one question from Q5 and Q6
5 (a) Explain the following terms:
i) Zeroth law of thermodynamics
ii) Extensive properties
iii) Closed system
iv) Heat engine.(4 marks) 5 (b) Explain measurement of pressure using simple U-tube manometer.(4 marks) 5 (c) A heat pump is used to maintain the house at 24 degree C. The house is losing the heat at the rate of 1800 kJ/min to the surrounding. The heat pump is driven by an electric motor of power rating 12 kW. Find:
i) The amount of heat absorbed from surrounding
ii) COP of the heat pump.
Draw the sketch of the system.(5 marks) 6 (a) The pressure of gas flowing through a pipe is to be measured with simple U-tube mercury manometer. Left arm of the U-tube is connected gas pipe while right arm is open to atmosphere. Calculate the absolute pressure of the gas when the level of mercury, in the arm open to atmosphere is:
Case (A) 300 mm higher than the level of mercury in left arm and
Case (B) 200 mm lower than the level of mercury in left arm.
Draw sketch of the system for Case (A) and Case (B).
Atmospheric pressure = 10 m of water column
Acceleration due to gravity = 9.81 m/sec2.
Density of mercury = 13600 kg/m3.(6 marks) 6 (b) Explain 'Kelvin-Planck and Clausius' statement of second law of thermodynamics.(4 marks) 6 (c) Draw a sketch of Heat Pump and Refrigerator using Heat Source and Sink concept.
(COP)Heat Pump=1+(COP)Refrigerator.(3 marks)
Solve any one question from Q7 and Q8
7 (a) Draw a layout of solar plant. State the limitations of the plant.(4 marks) 7 (b) Explain classification of boilers in brief.(4 marks) 7 (c) What do you mean by air-conditioning? Draw a neat sketch of window air-conditioning system. Show the direction of hot and cool air-flow.(5 marks) 8 (a) Draw a layout of hydro-electric power plant and explain the energy extraction (energy conversion) process.(4 marks) 8 (b) Differentiate between Impulse turbine and Reaction turbine (4 points).(4 marks) 8 (c) Explain working of reciprocating pump with neat diagram and state its application.(5 marks)