View note:ME---Mechanical-Engineering



Questions of this subject!.

QuestionLikes!Dislikes!Answers!
1)What is the Poissions ratio of an elastic incompressible material

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2)Find the velocity of molten metal at the bottom of sprue.

101
3)A heat pump is transferring 10 kW from a reservoir at 200 K to a reservoir at 300 K.

101
4)For an incompressible flow through a pipe of constant diameter in the fully developed region the mean velocity ios constant. What about the mean velocity in developing region?

102
5)In a steam condenser the inlet and exit temperature of the odd stream are 20 and the steam condenses on outside surface of the tube.

201
6)Which of the following is not a rotary machinery

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7)Find the minimum power required to maintain the flow of liquid in a pipe for a pressure drop of 100 kPa.

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8)What is the maximum shear stress induced in the shaft of diameter 40 mm.

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9)In stress strain curve of mild steel Ultimate Tensile Stress is

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10)Adiabatic work of 200 kJ is done on ideal gas of mass m = 1 kg (Cv=1000 j/kgk ), which is stored in a rigid container at a pressure of 100 kPa and temperature 300 K.

201
11)(0, 3)(0.5, 4)(1, 5) are points on the function f(x). the difference in value of the function f(x)

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12)In a gas turbine the pressure ratio is 10. Temperature of gas at the inlet of turbine is 300 K.

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13)A fair six faced die is rolled many times.

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14)A motor is driving a solid circular steel shaft transmits 40kW of power at 500 rpm. If the diameter of the shaft is 40 mm, The maximum shear stress in the shaft is ____ MPa.

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15) Metric thread of 0.8 mm pitch is to be cut on a lathe. Pitch of the lead screw is 1.5 mm. If the spindle rotates at 1500 rpm, the speed of rotation of the lead screw (rpm) will be ________

201
16)The molar specific heat at constant volume of an ideal gas is equal to 2.5 times the universal gas constant (8.314 J/mol.K). When the temperature increases by 100k, the change in molar specific enthalpy is ___ J/mol.

201
17)The poisson’s ratio for a perfectly incompressible linear material is

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18)A heat pump absorbs 10kW of heat from outside environment at 250 K while absorbing 15 kW of work. It delivers the heat to a room that must be kept warm at 300K. The coefficient of Performance (COP) of the heat pump is _________.

201
19)Which one of the following is NOT a rotating machine?

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20)Water (density =1000 kg/m3) at ambient temperature flows through a horizontal pipe of uniform cross section at the rate of 1 kg/s. If the pressure drop across the pipe is 100 kPa, the minimum power required to pump the water across the pipe, in watts, is _______

201
21)For steady flow of a viscous incompressible fluid through a circular pipe of constant diameter, the average velocity in the fully developed region is constant. Which one of the following statements about the average velocity in the developing region is TRUE?

201
22)In an arc welding process, welding speed is doubled. Assuming all other process parameters to be constant, the cross sectional area of the weld bead will

201
23)A six-face fair dice is rolled a large number of times. The mean value of the outcomes is ______.

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24)Consider a beam with circular cross-section of diameter d. The ratio of the second moment of area about the neutral axis to the section modulus of the area is.

201
25)Saturated steam at 100°C condenses on the outside of a tube. Cold fluid enters the tube at 20° C and exists at 50°C. The value of the Log Mean Temperature Difference (LMTD) is ________°C.

202
26)In the engineering stress-strain curve for mild steel, the Ultimate Tensile Strength (UTS) refers to

201
27)For an inline slider-crank mechanism, the lengths of the crank and connecting rod are 3m and 4m, respectively. At the instant when the connecting rod is perpendicular to the crank, if the velocity of the slider is 1m/s, the magnitude of angular velocity (upto 3 decimal points accuracy) of the crank is _________ radian/s.

201
28)Moist air is treated as an ideal gas mixture of water vapor and dry air (molecular weight of air = 28.84 and molecular weight of water = 18). At a location, the total pressure is 100 kPa, the temperature is 30°C and the relative humidity is 55%. Given that the saturation pressure of water at 30°C is 4246 Pa, the mass of water vapor per kg of dry air is _____________ grams

101
29)Moist air is treated as an ideal gas mixture of water vapor and dry air (molecular weight of air = 28.84 and molecular weight of water = 18). At a location, the total pressure is 100 kPa, the temperature is 30°C and the relative humidity is 55%. Given that the saturation pressure of water at 30°C is 4246 Pa, the mass of water vapor per kg of dry air is _____________ grams

101
30)Moist air is treated as an ideal gas mixture of water vapor and dry air (molecular weight of air = 28.84 and molecular weight of water = 18). At a location, the total pressure is 100 kPa, the temperature is 30°C and the relative humidity is 55%. Given that the saturation pressure of water at 30°C is 4246 Pa, the mass of water vapor per kg of dry air is _____________ grams.

101
31)Moist air is treated as an ideal gas mixture of water vapor and dry air (molecular weight of air = 28.84 and molecular weight of water = 18). At a location, the total pressure is 100 kPa, the temperature is 30°C and the relative humidity is 55%. Given that the saturation pressure of water at 30°C is 4246 Pa, the mass of water vapor per kg of dry air is _____________ grams.

101
32)Moist air is treated as an ideal gas mixture of water vapor and dry air (molecular weight of air = 28.84 and molecular weight of water = 18). At a location, the total pressure is 100 kPa, the temperature is 30°C and the relative humidity is 55%. Given that the saturation pressure of water at 30°C is 4246 Pa, the mass of water vapor per kg of dry air is _____________ grams.

101
33)Two models, P and Q, of a product earn profits of Rs. 100 and Rs. 80 per piece, respectively. Production times for P and Q are 5 hours and 3 hours, respectively, while the total production time available is 150 hours. For a total batch size of 40, to maximize profit, the number of units of P to be produced is ____________.

201
34)Moist air is treated as an ideal gas mixture of water vapor and dry air (molecular weight of air = 28.84 and molecular weight of water = 18). At a location, the total pressure is 100 kPa, the temperature is 30°C and the relative humidity is 55%. Given that the saturation pressure of water at 30°C is 4246 Pa, the mass of water vapor per kg of dry air is _____________ grams.

101
35)A 10 mm deep cylindrical cup with diameter of 15mm is drawn from a circular blank. Neglecting the variation in the sheet thickness, the diameter (upto 2 decimal points accuracy) of the blank is _________ mm.

201
36)A sprue in a sand mould has a top diameter of 20mm and height of 200mm. The velocity of the molten metal at the entry of the sprue is 0.5m/s. Assume acceleration due to gravity as 9.8 m/s2 and neglect all losses. If the mould is well ventilated, the velocity (upto 3 decimal points accuracy) of the molten metal at the bottom of the sprue is ________ m/s.

201
37)Air contains 79% N2 and 21% O2 on a molar basis. Methane (CH4) is burned with 50% excess air than required stoichiometrically. Assuming complete combustion of methane, the molar percentage of N2 in the products is ________________

101
38)A block of length 200mm is machined by a slab milling cutter 34mm in diameter. The depth of cut and table feed are set at 2mm and 18mm/minute, respectively. Considering the approach and the over travel of the cutter to be same, the minimum estimated machining time per pass is _____________ minutes.

201
39)In a company with 100 employees, 45 earn Rs. 20,000 per month, 25 earn Rs. 30,000, 20 earn Rs. 40,000,8 earn Rs. 60,000, and 2 earn Rs. 150,000. The median of the salaries is

301
40)As the two speakers became increasingly agitated, the debate became __________.

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41)P,Q, and R talk about S‟s car collection. P states that S has at least 3 cars. Q believes that S has less than 3 cars. R indicates that to his knowledge, S has at least one Car. Only one of P, Q and R is right the number cars owned by S is.

201
42)Which one of the following statements is TRUE for the ultrasonic machining (USM) process?

201
43)The emissive power of a blackbody is P. If its absolute temperature is doubled, the emissive power becomes

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44)The determinant of a 2x2 matrix is 50. If one eigenvalue of the matrix is 10, the other eigenvalue is

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45)Which one of the following statement is TRUE?

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46)It is desired to make a product having T-shaped cross-section from a rectangular aluminium block. Which one of the following processes is expected to provide the highest strength of the product?

201
47)The heat loss from a fin in 6W. The effectiveness and efficiency of the fin are 3 and 0.75, respectively. The heat loss (in W) from the fin, keeping the entire fin surface at base temperature, is ________.

201
48)For a single with Poisson arrival and exponential service time, the arrival rate is 12 per hour. Which one of the following service rates will provide a steady state finite queue length?

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49)For the stability of a floating body the

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50)The divergence of the vector −yi+xj______

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51)If a mass of moist air contained in a closed metallic vessel is heated, then its

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52)The crystal structure of aluminium is

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53)Given the atomic weight of Fe is 56 and that of C is 12, the weight percentage of carbon in cementite (Fe3C) is ________

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54)In an orthogonal machining with a tool of 9° orthogonal rake angle, the uncut chip thickness is 0.2mm. The chip thickness fluctuates between 0.25 mm and 0.4 mm. The ratio of the maximum shear angel to the minimum shear angle during machining is _________

201
55)In a counter-flow heat exchanger, water is heated at the rate of 1.5kg/s from 40°C to 80°C by an oil entering at 120°C and leaving at 60°C. The specific heats of water and oil are 4.2kJ/kg/K and 2kJ/kg.K respectively. The overall heat transfer coefficient is 400 W/m2 .K. The required heat transfer surface area (in m2) is

201
56)In a counter-flow heat exchanger, water is heated at the rate of 1.5kg/s from 40°C to 80°C by an oil entering at 120°C and leaving at 60°C. The specific heats of water and oil are 4.2kJ/kg/K and 2kJ/kg.K respectively. The overall heat transfer coefficient is 400 W/m2 .K. The required heat transfer surface area (in m2) is

101
57)A rod of length 20mm is stretched to make a rod of length 40 mm. Subsequently, it is compressed to make a rod of final length 10 mm. Consider the longitudinal tensile strain as positive and compressive strain as negative. The total true longitudinal strain in the rod is _______

201
58)In the Rankine cycle for a steam power plant the turbine entry and exit enthalpies are 2803 kJ/kg and 1800 kJ/kg, respectively. The enthalpies of water at pump entry and exit are 121 kJ/kg and 124 kJ/kg, respectively. The specific steam consumption (in kg/k W.h) of the cycle is _______

202
59)A calorically perfect gas (specific heat at constant pressure 1000 J/kg.K) enters and leaves a gas turbine with the same velocity. The temperatures of the gas at turbine entry and exit are 1100 K and 400 K, respectively. The power produced is 4.6 MW and heat escapes at the rate of 300 kJ/s through the turbine casing. The mass flow rate of the gas (in kg/s) through the turbine is

201
60)A strip of 120 mm width and 8 mm thickness is rolled between two 300 mm-diameter rolls to get a strip of 120 mm width and 7.2 mm thickness. The speed of the strip at the exit is 30 m/min. There is no front or back tension. Assuming uniform roll pressure of 200 MPa in the roll bite and 100% mechanical efficiency, the minimum total power (in kW) required to drive the two roll is _______.

101
61)One kg of an ideal gas (gas constant R=287 J/kg.K) undergoes an irreversible process from state-1 (1 bar, 300 K) to state -2 (2 bar, 300 K). The change in specific entropy (s1-s2) of the gas (in J/kg.K) in the process is

201
62)FACE and SIZE are the attributes of _______ tag .

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63)Let G be a group with 15 elements. Let L be a subgroup of G. It is known that L≠G and that the size of L is at least 4. The size of L is _______. - Gate Computer Science 2014

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