SILVER OAK COLLEGE OF ENGINEERING & TECHNOLOGY ADITYA SILVER OAK INSTITUTE OF TECHNOLOGY

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1 SUBJECT: ENGINEERING THERMODYNAMICS ( ) (ME) DATE: TIME: 10:00 am to 11:30 am TOTAL MARKS: 40 Q.1 (a) Answer following questions in short/brief: 1. Energy of an isolated system is always constant. Justify the statement. 2. Define Steady and Unsteady flow process. 3. Define control volume in brief. 4. Define PMM1. 5. Justify the statement: For high altitudes or space applications we use microscopic Approach. (b) Compare Otto, Diesel and Dual cycle for i) Same compression ratio and heat supplied ii) Same Max. Pressure and temperature Q.2 (a) In an I C Engine working with the Otto cycle, the cylinder diameter is 250mm and a stroke is 375mm. If the clearance volume is m 3, and the initial pressure and temperature are 1bar and C, calculate the air standard efficiency and mean effective pressure of the cycle. The maximum cycle pressure is limited to 25bar. (b) Explain the effect of regeneration on brayton cycle. (c) Explain Quasi static process in brief with neat sketch. Q.2 (a) A closed cycle ideal gas turbine plant operates between temperature limits of 800 C and 30 C and produces a power of 100 kw. The plant is designed such that there is no need for a regenerator. A fuel of calorific 45000kJ/kg is used. Calculate the mass flow rate of air through the plant and rate of fuel consumption.

2 Assume cp = 1 kj/kg K and γ = 1.4. (b) Derive Equation of air standard efficiency for Otto cycle. (c) Prove that Energy is a property of system. Q.3 (a) The air compressor takes in air steadily at the rate of 0.6 kg/sec from the surroundings with pressure of 100.0kPa and density of kg/m3. The air entry velocity is 7.0 m/sec. The pressure ratio of air compressor is 7.0. The leaving air has density of kg/m3 and leaves with velocity of 5.0 m/sec. The internal energy of the leaving air is 100.0kJ/kg more than that at entering. Cooling water in the compressor jackets absorbs heat from air at the rate of 65.0 kw. i) Compute the rate of shaft work to air ii) Find the ratio of inlet pipe diameter to outlet pipe diameter (b) Derive the equation for filling of a tank/bottle. (c) Define the following terms in short : 1.Thermodynamic equilibrium 2.Intensive and Extensive properties Q.3 (a) Air enters an insulated nozzle at 300 kpa, 500 K with a velocity of 10m/s. It leaves the nozzle at 100 kpa with a velocity of 180 m/s. The Inlet area is 80 cm 2. The specific heat of air is 1005 J/kgK. Treat air as an ideal gas. i) Find the exit temperature of the air. ii) Find the exit area of the nozzle. (b) Explain Joule s Experiment. (c) Explain Different types of Systems with Examples.

3 SUBJECT: KINEMATICS OF MACHINES ( ) (ME) DATE: TIME: 10:00 am to 11:30 am TOTAL MARKS: 40 Q.1 (a) Explain the terms in relation to gears: (1) Module (2) Circular Pitch (3) Pressure Angle (4) Backlash (5) Contact ratio (b) Explain degree of freedom with neat sketch. Also explain Grubler s criterion and State Grashof s law. Q.2 (a) In a four bar chain ABCD, AD is fixed and is 150 mm long. The crank AB is 40 mm long and rotates at 120 r.p.m. clockwise, while the link CD = 80 mm oscillates about D. BC and AD are of equal length. Find the angular velocity of link CD and link BC when angle BAD = 60. (b) Explain Difference Between Whitworth quick return motion mechanism and Crank & Slotted quick return motion mechanism with neat sketch. (c) Differentiate between Machine and Structure with suitable example. Q.2 (a) The crank and connecting rod of a theoretical steam engine are 0.5 m and 2 m long respectively. The crank makes 180 r.p.m. in the clockwise direction. When it has turned 45 from the inner dead centre position, determine : 1. Velocity of piston, 2. Angular velocity of connecting rod, 3. Velocity of point E on the connecting rod 1.5 m from the gudgeon pin. (b) Explain different types of constrained motions with neat sketch. (c) A crank and slotted lever mechanism used in a shaper has a centre distance of 300mm between the centre of oscillation of the slotted lever and the centre of Rotation of the crank. The radius of the cranks is 120mm.Find the ratio of the Time of cutting to the time of return stroke. Q.3 (a) In an epicyclic gear train, an arm carries two gears A and B having 36 and 45 teeth respectively. If the arm rotates at 150 r.p.m. in the anticlockwise direction about the centre of the gear A which is fixed, Determine the speed of gear B. If the gear A instead of being fixed, makes 300 r.p.m. in the clockwise direction what will be the speed if gear B? (b) Give Classification of Gears. (c) A pinion having 30 teeth drives a gear having 80 teeth. The profile of gear is involute with 20 0 pressure angle, 12 mm module and 10 mm addendum. Find the contact ratio.

4 Q.3 (a) Derive an expression for the length of path of contact for two involutes profile gear in mesh. (b) Derive an equation for minimum number of teeth on pinion to Avoid Interference with wheel. (c) Enlist different type of gear train.explain compound gear train with neat sketch.also derive the equation of the velocity ratio for compound gear train.

5 SUBJECT: MECHANICS OF SOLIDS ( ) (ME/CL/AE) DATE: TIME: 10:00 am to 11:30 am TOTAL MARKS: Refer the figure numbers as mentioned in the questions. Q.1 (a) Define the following terms: 1. Hooke s law 2. Modulus of Rigidity 3. Poisson s Ratio 4. Coplanar Non-Concurrent Forces 5. Principle of Transmissibility (b) State and explain the law of parallelogram of forces. Q.2 (a) Determine magnitude, direction & perpendicular distance from O of the resultant for the force system as shown in Figure 1. (b) Find the resultant of given force system. Also find direction of the resultant as shown in the Figure 2. (c) Prove the notation Q.2 (a) For system shown in Figure 3, if a cylinder A weight 20KN. Find weight of B and force on each chord so that the system remain in equilibrium. (b) Determinate the magnitude and direction of resultant force of the force system as shown in Figure 4. (c) State and explain Lami s theorem. Q.3 (a) A stepped bar made of steel, copper and brass is under axial force as shown in Figure 5 and is in equilibrium. The diameter of steel is 12mm, diameter of copper is 16mm and diameter of brass is 20mm. Determine: i) Magnitude of unknown force P, ii) Stresses in each material and iii) Total change in length of the bar. Take ESTEEL =200GPa, ECOPPER=100GPa, EBRASS=80GPa. (b) A steel rod of 100mm diameter is inserted into copper tube of 200mm external diameter and 100mm internal diameter. The composite section is subjected to axial tensile force of 100kN. Length of section is 0.5m. ES =2.1 X 10 5 N/mm 2, EC=1.3 X 10 5 N/mm 2. Calculate stresses in each material. (c) A system of four forces shown in Figure 6 has resultant 50N along X-axis. Determine magnitude & inclination of unknown force P.

6 Q.3 (a) An assembly made up from aluminum and steel bars as shown in Figure 7, is initially stress free at temperature 32 C. The assembly is heated to bring its temperature to 82 C. Find the stresses developed in each bar. The coefficients of thermal expansions are & for steel and aluminum respectively. Take ES= 200 GPa & EA= 75 GPa. (b) A load of 2000 kn is applied on a short concrete column, reinforced with four nos. of 10 mm diameter steel bars. Find stresses in concrete and steel. Take value of E of steel as and for concrete. (c) A circular rod of diameter 20mm and 500mm long is subjected to a tensile force of 50kN. The modulus of elasticity for steel may be taken as 200kN/mm 2. Find stress, strain and elongation of the bar due to applied load. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

7 SUBJECT: MANUFACTURING PROCESS - I ( ) (ME) DATE: TIME: 10:00 am to 11:30 am TOTAL MARKS: 40 Q.1 (a) 1) What is working principle of Lathe Machine? 2) Define following term: Speed and Feed 3) Which material used for machine bed? Justify your answer. 4) Can we perform drilling operation on lathe? (Yes or No) Gives justification of your answer. 5) Gives the components name which are used for alignment test. (b) Define a Basic Machine Tool and Classify them. What are the general requirements of machine tools? Q.2 (a) Draw front view, top view and side view of single point cutting tool. Indicate all elements and important angles on it. Identify following tool signature (b) Differentiate between Capstan and Turret lathe. (c) Write short note on different type of chucks used in a lathe. Q.2 (a) List out the different types of taper turning methods and explain any one with neat sketch. (b) What are the different operations performed on a lathe? Explain any four operations. (c) What are the essential differences between steady rest and follow rest? Q.3 (a) Draw a neat sketch of a radial drilling machine and name the important parts. What are advantages of radial drilling machine? (b) Explain different types of reamers used in drilling. (c) Differentiate between counter boring and counter sinking. Q.3 (a) Explain different operations performed with the help of a drilling machine. (b) What could be the possible causes for the following drilling problems? (i) Breaking of drill (ii) Hole too large (iii) production of rough hole and (iv) Breaking down of outer corner of cutting edges. (c) Write various applications of Drilling and Boring operations.

8 SUBJECT: MATERIAL SCIENCE & METALLURGY ( ) (ME) DATE: TIME: 10:00 am to 11:30 am TOTAL MARKS:40 Q.1 (a) Define. 1)Unit Cell 2)Grain Boundary 3)Coordination Number 4)Crystal Structure 5)Dislocation (b) Explain Criteria for Selection of Engineering Material Q.2 (a) Explain Various Point Defects in the crystals with neat sketch. (b) Explain the Mechanism of Recovery and Recrystallization. (c) Explain any three types of Solidification Defects. Page 1 of Enroll. No. SUBJECT: MATERIAL SCIENCE & METALLURGY ( ) (ME) DATE: TIME: 10:00 am to 11:30 am TOTAL MARKS:40 Q.1 (a) Define. 1)Unit Cell 2)Grain Boundary 3)Coordination Number 4)Crystal Structure 5)Dislocation (b) Explain Criteria for Selection of Engineering Material Q.2 (a) Explain Various Point Defects in the crystals with neat sketch. (b) Explain the Mechanism of Recovery and Recrystallization. (c) Explain any three types of Solidification Defects. Page 1 of 2

9 Q.2 (a) Find the Atomic Packing Factor for S.C, B.C.C, F.C.C. Crystal Structure. (b) Differentiate between Edge and Screw dislocation with sketch. (c) Draw the following planes (a) (113) (b) (102) (c) (111) and (d) (001). Q.3 (a) Differentiate between Homogeneous and Heterogeneous nucleation processes. Also discuss the conditions under which growth may be of planar and dendritic type. (b) Give the difference between slip and twinning mechanisms using sketch. (c) What is Gibbs Phase Rule and define Degree of freedom, Phase, Component. Q.3 (a) Explain the strain hardening process. Also mention the effect of strain hardening on properties of metals. (b) What is critical radius and derive the value for the critical radius? (c) What is Solid Solution? Explain Hume Rothery Rules Page 2 of 2 Q.2 (a) Find the Atomic Packing Factor for S.C, B.C.C, F.C.C. Crystal Structure. (b) Differentiate between Edge and Screw dislocation with sketch. (c) Draw the following planes (a) (113) (b) (102) (c) (111) and (d) (001). Q.3 (a) Differentiate between Homogeneous and Heterogeneous nucleation processes. Also discuss the conditions under which growth may be of planar and dendritic type. (b) Give the difference between slip and twinning mechanisms using sketch. (c) What is Gibbs Phase Rule and define Degree of freedom, Phase, Component. Q.3 (a) Explain the strain hardening process. Also mention the effect of strain hardening on properties of metals. (b) What is critical radius and derive the value for the critical radius? (c) What is Solid Solution? Explain Hume Rothery Rules. Page 2 of 2

10 BE - SEMESTER 3 MID SEMESTER-I EXAMINATION WINTER 2017 SUBJECT: Advanced Engineering Mathematics ( ) (All Branches) DATE: TIME:10:00 am to 11:45 am TOTAL MARKS:40 1.Q. 1 is compulsory. Q.1 (a) Short Questions. (i) 3t 3 Find L{ e } (ii) Find the Convolution of 1*1 (iii) State the relationship between beta and gamma function. (iv) Define Heaviside s unit step function (v) Define Fourier series for even & odd function (b) Obtain the following function by Convolution Theorem L 1 1 ( (s 2)(s + 2) 2) Q.2 (a) Solve the differential equation using Laplace Transform: y 2y = e t sint, y 0 = y 0 = 0 (b) Obtain the Inverse Laplace transform of following function L 1 ln 1 + w 2 s 2 (c) Solve the following function by Laplace Transform f(t) = t 2 sinπt Q.2 (a) Solve the differential equation using Laplace Transform y" 3y + 2y = 12e 2t, y(0) = 2, y (0) = 6 (b) Obtain the Inverse Laplace Transform of following functions L 1 s (s+1)(s 1) 2 (c) Obtain the Laplace Transform (By Integral Property) L 0 t e u u + sinu du Q.3 (a) Find the Fourier series expansion for the 2π-periodic function f x = x x 2 in the interval π x π and show that = π2 12

11 (b) Obtain Fourier Series of f( x)= π + x, -π < x < 0 = π x, 0 < x < π (c) Find the Fourier cosine integral of f(x) = e -x x 0 Q.3 (a) Obtain the Fourier series to represent the function 1 2 f ( x) ( x),0 x 2 4 (b) Find the Fourier series of f ( x) x x where x (, ) (c) sin x Express the function f (x) 0 and evaluate sin x sin d x as a Fourier sine integral x BEST OF LUCK