Page 1 GATE ME - 1998 SECTION - A 1. This question consists of TWENTY-FIVE sub-questions (1.1 – 1.25) of ONE mark each. For each of these sub-questions, four possible alternatives (A, B, C and D) are given, out of which ONLY ONE is correct. Indicate the correct answer by darkening the appropriate bubble against the question number on the left hand side of the Objective Response Sheet (ORS). You may use the answer book provided for any rough work, if needed. 1.1 For , 6 x p = the sum of the series ( ) 2 2 4 1 cos cos cos n x x x 8 = + + ? Kis (a) p (b) 3 (c) 8 (d) 1 1.2 ( ) 2 1 s - + is the Laplace transform of (a) 2 t (b) 3 t (c) 2t e - (d) t te - 0?0 1.3 ( ) 2 0 If , x x tdt F = ? then d dx F is: (a) 2 2x (b) x (c) 0 (d) 1 1.4 The magnitude of the gradient of the function ( ) 3 at 1,0,2 f xyz = is: (a) 0 (b) 3 (c) 8 (d) 8 1.5 The probability that two friends share the same birth-month is: (a) 1 6 (b) 1 12 (c) 1 144 (d) 1 24 1.6 A car moving with uniform acceleration covers 450 m in a 5 second interval, and covers 700 m in the next 5 second interval. The acceleration of the car is: (a) 7 m/s 2 (b) 50 m/s 2 (c) 25 m/s 2 (d) 10 m/s 2 1.7 The buckling load for a column pinned at both ends is 10 kN. If the ends are fixed, the buckling load changes to (a) 40 kN (b) 2.5 kN (c) 5 kN (d) 20 k N 1.8 The normal stresses at a point are 10 MPa x s = and, 2 MPa; y s = the shear stress at this point is 4 MPa. The maximum principal stress at this point is: (a) 16 MPa (b) 14 MPa (c) 11 MPa (d) 10 MPa Page 2 GATE ME - 1998 SECTION - A 1. This question consists of TWENTY-FIVE sub-questions (1.1 – 1.25) of ONE mark each. For each of these sub-questions, four possible alternatives (A, B, C and D) are given, out of which ONLY ONE is correct. Indicate the correct answer by darkening the appropriate bubble against the question number on the left hand side of the Objective Response Sheet (ORS). You may use the answer book provided for any rough work, if needed. 1.1 For , 6 x p = the sum of the series ( ) 2 2 4 1 cos cos cos n x x x 8 = + + ? Kis (a) p (b) 3 (c) 8 (d) 1 1.2 ( ) 2 1 s - + is the Laplace transform of (a) 2 t (b) 3 t (c) 2t e - (d) t te - 0?0 1.3 ( ) 2 0 If , x x tdt F = ? then d dx F is: (a) 2 2x (b) x (c) 0 (d) 1 1.4 The magnitude of the gradient of the function ( ) 3 at 1,0,2 f xyz = is: (a) 0 (b) 3 (c) 8 (d) 8 1.5 The probability that two friends share the same birth-month is: (a) 1 6 (b) 1 12 (c) 1 144 (d) 1 24 1.6 A car moving with uniform acceleration covers 450 m in a 5 second interval, and covers 700 m in the next 5 second interval. The acceleration of the car is: (a) 7 m/s 2 (b) 50 m/s 2 (c) 25 m/s 2 (d) 10 m/s 2 1.7 The buckling load for a column pinned at both ends is 10 kN. If the ends are fixed, the buckling load changes to (a) 40 kN (b) 2.5 kN (c) 5 kN (d) 20 k N 1.8 The normal stresses at a point are 10 MPa x s = and, 2 MPa; y s = the shear stress at this point is 4 MPa. The maximum principal stress at this point is: (a) 16 MPa (b) 14 MPa (c) 11 MPa (d) 10 MPa GATE ME - 1998 1.9 The ratio of average shear stress to the maximum shear stress in a beam with a square cross-section is: (a) 1 (b) 2 3 (c) 3 2 (d) 2 1.10 Heat transfer coefficient for free convection in gases, forced convection in gases and vapours, and for boiling water lie, respectively in the ranges of (a) 5 – 15, 20 – 200 and 3000 – 50,000 W/m 2 K. (b) 20 – 50, 200 – 500 and 50,000 – 10 5 W/m 2 K. (c) 50 – 100, 500 – 1000 and 10 5 – 10 6 W/m 2 K. (d) 20 – 100, 200 – 1000, and a constant 10 6 W/m 2 K. 1.11 If N V and a are the nozzle exit velocity and nozzle angle in an impulse turbine, the optimum blade velocity is given by (a) cos2 N V a (b) sin2 N V a (c) cos 2 N V a (d) 2 2 N V 1.12 A Curtis stage, Rateau stage and a 50% reaction stage in a steam turbine are examples of (a) different types of impulse stages (b) different types of reaction stages (c) a simple impulse stage, a velocity compounded impulse stage and reaction stage (d) a velocity compounded impulse stage, a simple impulse stage and a reaction stage 1.13 The basic load rating of a ball bearing is (a) the maximum static radial load that can be applied without causing any plastic deformation of bearing component. (b) the radial load at which 90% of the group of apparently identical bearings run for one million revolutions before the first evidence of failure. (c) the maximum radial load that can be applied during operation without any plastic deformation of bearing components. (d) a combination of radial and axial loads that can be applied without any plastic deformation. 1.14 Decreasing grain size in a polycrystalline material (a) increases yield strength and corrosion resistance (b) decreases yield strength and corrosion resistance (c) decreases yield strength but increases corrosion resistance (d) increases yield strength but decreases corrosion resistance. Page 3 GATE ME - 1998 SECTION - A 1. This question consists of TWENTY-FIVE sub-questions (1.1 – 1.25) of ONE mark each. For each of these sub-questions, four possible alternatives (A, B, C and D) are given, out of which ONLY ONE is correct. Indicate the correct answer by darkening the appropriate bubble against the question number on the left hand side of the Objective Response Sheet (ORS). You may use the answer book provided for any rough work, if needed. 1.1 For , 6 x p = the sum of the series ( ) 2 2 4 1 cos cos cos n x x x 8 = + + ? Kis (a) p (b) 3 (c) 8 (d) 1 1.2 ( ) 2 1 s - + is the Laplace transform of (a) 2 t (b) 3 t (c) 2t e - (d) t te - 0?0 1.3 ( ) 2 0 If , x x tdt F = ? then d dx F is: (a) 2 2x (b) x (c) 0 (d) 1 1.4 The magnitude of the gradient of the function ( ) 3 at 1,0,2 f xyz = is: (a) 0 (b) 3 (c) 8 (d) 8 1.5 The probability that two friends share the same birth-month is: (a) 1 6 (b) 1 12 (c) 1 144 (d) 1 24 1.6 A car moving with uniform acceleration covers 450 m in a 5 second interval, and covers 700 m in the next 5 second interval. The acceleration of the car is: (a) 7 m/s 2 (b) 50 m/s 2 (c) 25 m/s 2 (d) 10 m/s 2 1.7 The buckling load for a column pinned at both ends is 10 kN. If the ends are fixed, the buckling load changes to (a) 40 kN (b) 2.5 kN (c) 5 kN (d) 20 k N 1.8 The normal stresses at a point are 10 MPa x s = and, 2 MPa; y s = the shear stress at this point is 4 MPa. The maximum principal stress at this point is: (a) 16 MPa (b) 14 MPa (c) 11 MPa (d) 10 MPa GATE ME - 1998 1.9 The ratio of average shear stress to the maximum shear stress in a beam with a square cross-section is: (a) 1 (b) 2 3 (c) 3 2 (d) 2 1.10 Heat transfer coefficient for free convection in gases, forced convection in gases and vapours, and for boiling water lie, respectively in the ranges of (a) 5 – 15, 20 – 200 and 3000 – 50,000 W/m 2 K. (b) 20 – 50, 200 – 500 and 50,000 – 10 5 W/m 2 K. (c) 50 – 100, 500 – 1000 and 10 5 – 10 6 W/m 2 K. (d) 20 – 100, 200 – 1000, and a constant 10 6 W/m 2 K. 1.11 If N V and a are the nozzle exit velocity and nozzle angle in an impulse turbine, the optimum blade velocity is given by (a) cos2 N V a (b) sin2 N V a (c) cos 2 N V a (d) 2 2 N V 1.12 A Curtis stage, Rateau stage and a 50% reaction stage in a steam turbine are examples of (a) different types of impulse stages (b) different types of reaction stages (c) a simple impulse stage, a velocity compounded impulse stage and reaction stage (d) a velocity compounded impulse stage, a simple impulse stage and a reaction stage 1.13 The basic load rating of a ball bearing is (a) the maximum static radial load that can be applied without causing any plastic deformation of bearing component. (b) the radial load at which 90% of the group of apparently identical bearings run for one million revolutions before the first evidence of failure. (c) the maximum radial load that can be applied during operation without any plastic deformation of bearing components. (d) a combination of radial and axial loads that can be applied without any plastic deformation. 1.14 Decreasing grain size in a polycrystalline material (a) increases yield strength and corrosion resistance (b) decreases yield strength and corrosion resistance (c) decreases yield strength but increases corrosion resistance (d) increases yield strength but decreases corrosion resistance. GATE ME - 1998 1.15 Auto collimator is used to check (a) roughness (b) flatness (c) angle (d) automobile balance 1.16 Failure of a bead weld between a heavy steel section and a thin section is mainly due to the formation of (a) spheroidite (b) bainite (c) carbon free zone due to burning of carbon at high temperature (d) martensite. 1.17 Ideal surface roughness, as measured by the maximum height of unevenness, is best achieved when the material is removed by (a) an end mill (b) a grinding wheel (c) a tool with zero nose radius (d) a ball mill 1.18 In the specification of dimensions and fits, (a) allowance is equal to bilateral tolerance (b) allowance is equal to unilateral tolerance (c) allowance is independent of tolerance (d) allowance is equal to the difference between maximum and minimum dimension specified by the tolerance. 1.19. In machining using abrasive material, increasing abrasive grain size (a) increases the material removal rate (b) decreases the material removal rate (c) first decreases and then increases the material removal rate (d) first increases and then decreases the material removal rate 1.20. With increasing temperature of intake air, IC engine efficiency (a) decreases (b) increases (c) remains same (d) depends on other factors 1.21. Chills are used in moulds to (a) achieve directional solidification (b) reduce the possibility of blowholes (c) reduce freezing time (d) smoothen metal flow for reducing splatter. Page 4 GATE ME - 1998 SECTION - A 1. This question consists of TWENTY-FIVE sub-questions (1.1 – 1.25) of ONE mark each. For each of these sub-questions, four possible alternatives (A, B, C and D) are given, out of which ONLY ONE is correct. Indicate the correct answer by darkening the appropriate bubble against the question number on the left hand side of the Objective Response Sheet (ORS). You may use the answer book provided for any rough work, if needed. 1.1 For , 6 x p = the sum of the series ( ) 2 2 4 1 cos cos cos n x x x 8 = + + ? Kis (a) p (b) 3 (c) 8 (d) 1 1.2 ( ) 2 1 s - + is the Laplace transform of (a) 2 t (b) 3 t (c) 2t e - (d) t te - 0?0 1.3 ( ) 2 0 If , x x tdt F = ? then d dx F is: (a) 2 2x (b) x (c) 0 (d) 1 1.4 The magnitude of the gradient of the function ( ) 3 at 1,0,2 f xyz = is: (a) 0 (b) 3 (c) 8 (d) 8 1.5 The probability that two friends share the same birth-month is: (a) 1 6 (b) 1 12 (c) 1 144 (d) 1 24 1.6 A car moving with uniform acceleration covers 450 m in a 5 second interval, and covers 700 m in the next 5 second interval. The acceleration of the car is: (a) 7 m/s 2 (b) 50 m/s 2 (c) 25 m/s 2 (d) 10 m/s 2 1.7 The buckling load for a column pinned at both ends is 10 kN. If the ends are fixed, the buckling load changes to (a) 40 kN (b) 2.5 kN (c) 5 kN (d) 20 k N 1.8 The normal stresses at a point are 10 MPa x s = and, 2 MPa; y s = the shear stress at this point is 4 MPa. The maximum principal stress at this point is: (a) 16 MPa (b) 14 MPa (c) 11 MPa (d) 10 MPa GATE ME - 1998 1.9 The ratio of average shear stress to the maximum shear stress in a beam with a square cross-section is: (a) 1 (b) 2 3 (c) 3 2 (d) 2 1.10 Heat transfer coefficient for free convection in gases, forced convection in gases and vapours, and for boiling water lie, respectively in the ranges of (a) 5 – 15, 20 – 200 and 3000 – 50,000 W/m 2 K. (b) 20 – 50, 200 – 500 and 50,000 – 10 5 W/m 2 K. (c) 50 – 100, 500 – 1000 and 10 5 – 10 6 W/m 2 K. (d) 20 – 100, 200 – 1000, and a constant 10 6 W/m 2 K. 1.11 If N V and a are the nozzle exit velocity and nozzle angle in an impulse turbine, the optimum blade velocity is given by (a) cos2 N V a (b) sin2 N V a (c) cos 2 N V a (d) 2 2 N V 1.12 A Curtis stage, Rateau stage and a 50% reaction stage in a steam turbine are examples of (a) different types of impulse stages (b) different types of reaction stages (c) a simple impulse stage, a velocity compounded impulse stage and reaction stage (d) a velocity compounded impulse stage, a simple impulse stage and a reaction stage 1.13 The basic load rating of a ball bearing is (a) the maximum static radial load that can be applied without causing any plastic deformation of bearing component. (b) the radial load at which 90% of the group of apparently identical bearings run for one million revolutions before the first evidence of failure. (c) the maximum radial load that can be applied during operation without any plastic deformation of bearing components. (d) a combination of radial and axial loads that can be applied without any plastic deformation. 1.14 Decreasing grain size in a polycrystalline material (a) increases yield strength and corrosion resistance (b) decreases yield strength and corrosion resistance (c) decreases yield strength but increases corrosion resistance (d) increases yield strength but decreases corrosion resistance. GATE ME - 1998 1.15 Auto collimator is used to check (a) roughness (b) flatness (c) angle (d) automobile balance 1.16 Failure of a bead weld between a heavy steel section and a thin section is mainly due to the formation of (a) spheroidite (b) bainite (c) carbon free zone due to burning of carbon at high temperature (d) martensite. 1.17 Ideal surface roughness, as measured by the maximum height of unevenness, is best achieved when the material is removed by (a) an end mill (b) a grinding wheel (c) a tool with zero nose radius (d) a ball mill 1.18 In the specification of dimensions and fits, (a) allowance is equal to bilateral tolerance (b) allowance is equal to unilateral tolerance (c) allowance is independent of tolerance (d) allowance is equal to the difference between maximum and minimum dimension specified by the tolerance. 1.19. In machining using abrasive material, increasing abrasive grain size (a) increases the material removal rate (b) decreases the material removal rate (c) first decreases and then increases the material removal rate (d) first increases and then decreases the material removal rate 1.20. With increasing temperature of intake air, IC engine efficiency (a) decreases (b) increases (c) remains same (d) depends on other factors 1.21. Chills are used in moulds to (a) achieve directional solidification (b) reduce the possibility of blowholes (c) reduce freezing time (d) smoothen metal flow for reducing splatter. GATE ME - 1998 1.22. One of the following statements about PRS (Periodic Reordering System) is not true. Identify, (a) PRS requires continuous monitoring of inventory levels (b) PRS is useful in control of perishable items (c) PRS provides basis for adjustments to account for variations in demand (d) In PRS, inventory holding costs are higher than in Fixed Recorder Quantity System 1.23. In inventory planning, extra inventory is unnecessarily carried to the end of the planning period when using one of the following lot size decision policies: (a) Lot – for – lot production (b) Economic Order Quantity (EOQ) lot size (c) Period Order Quantity (POQ) lot size (d) Part Period total cost balancing 1.24. In a weaving operation, the parameter to be controlled is the number of defects per 10 square yards of material. Control chart appropriate for this task is (a) P - chart (b) C - chart (c) R - chart (d) X -Chart 1.25 Which one of the following forecasting techniques is not suited for making forecasts for planning production schedules in the short range? (a) Moving average (b) Exponential moving average (c) Regression analysis (d) Delphi 2. This question consists of TWENTY-FIVE sub-questions (2.1 – 2.25) of TWO marks each. For each of these sub-questions, four possible alternatives (A, B, C and D) are given, out of which ONLY ONE is correct. 2.1 The general solution of the differential equation 2 2 2 0 d y dy x x y dx dx - + = is: (a) 2 Ax Bx + (A,B are constants) (b) log Ax B x + (A,B are constants) (c) 2 log Ax Bx x + (A,B are constants) (d) log Ax Bx x + (A,B are constants) 2.2. The best fit line using least squares for the data (0,0), (10, 24), (20, 36) and (30,60) is: (a) 2x – y = 0 (b) 2x – y + 4 = 0 (c) 2x – y – 4 = 0 (d) None of these Page 5 GATE ME - 1998 SECTION - A 1. This question consists of TWENTY-FIVE sub-questions (1.1 – 1.25) of ONE mark each. For each of these sub-questions, four possible alternatives (A, B, C and D) are given, out of which ONLY ONE is correct. Indicate the correct answer by darkening the appropriate bubble against the question number on the left hand side of the Objective Response Sheet (ORS). You may use the answer book provided for any rough work, if needed. 1.1 For , 6 x p = the sum of the series ( ) 2 2 4 1 cos cos cos n x x x 8 = + + ? Kis (a) p (b) 3 (c) 8 (d) 1 1.2 ( ) 2 1 s - + is the Laplace transform of (a) 2 t (b) 3 t (c) 2t e - (d) t te - 0?0 1.3 ( ) 2 0 If , x x tdt F = ? then d dx F is: (a) 2 2x (b) x (c) 0 (d) 1 1.4 The magnitude of the gradient of the function ( ) 3 at 1,0,2 f xyz = is: (a) 0 (b) 3 (c) 8 (d) 8 1.5 The probability that two friends share the same birth-month is: (a) 1 6 (b) 1 12 (c) 1 144 (d) 1 24 1.6 A car moving with uniform acceleration covers 450 m in a 5 second interval, and covers 700 m in the next 5 second interval. The acceleration of the car is: (a) 7 m/s 2 (b) 50 m/s 2 (c) 25 m/s 2 (d) 10 m/s 2 1.7 The buckling load for a column pinned at both ends is 10 kN. If the ends are fixed, the buckling load changes to (a) 40 kN (b) 2.5 kN (c) 5 kN (d) 20 k N 1.8 The normal stresses at a point are 10 MPa x s = and, 2 MPa; y s = the shear stress at this point is 4 MPa. The maximum principal stress at this point is: (a) 16 MPa (b) 14 MPa (c) 11 MPa (d) 10 MPa GATE ME - 1998 1.9 The ratio of average shear stress to the maximum shear stress in a beam with a square cross-section is: (a) 1 (b) 2 3 (c) 3 2 (d) 2 1.10 Heat transfer coefficient for free convection in gases, forced convection in gases and vapours, and for boiling water lie, respectively in the ranges of (a) 5 – 15, 20 – 200 and 3000 – 50,000 W/m 2 K. (b) 20 – 50, 200 – 500 and 50,000 – 10 5 W/m 2 K. (c) 50 – 100, 500 – 1000 and 10 5 – 10 6 W/m 2 K. (d) 20 – 100, 200 – 1000, and a constant 10 6 W/m 2 K. 1.11 If N V and a are the nozzle exit velocity and nozzle angle in an impulse turbine, the optimum blade velocity is given by (a) cos2 N V a (b) sin2 N V a (c) cos 2 N V a (d) 2 2 N V 1.12 A Curtis stage, Rateau stage and a 50% reaction stage in a steam turbine are examples of (a) different types of impulse stages (b) different types of reaction stages (c) a simple impulse stage, a velocity compounded impulse stage and reaction stage (d) a velocity compounded impulse stage, a simple impulse stage and a reaction stage 1.13 The basic load rating of a ball bearing is (a) the maximum static radial load that can be applied without causing any plastic deformation of bearing component. (b) the radial load at which 90% of the group of apparently identical bearings run for one million revolutions before the first evidence of failure. (c) the maximum radial load that can be applied during operation without any plastic deformation of bearing components. (d) a combination of radial and axial loads that can be applied without any plastic deformation. 1.14 Decreasing grain size in a polycrystalline material (a) increases yield strength and corrosion resistance (b) decreases yield strength and corrosion resistance (c) decreases yield strength but increases corrosion resistance (d) increases yield strength but decreases corrosion resistance. GATE ME - 1998 1.15 Auto collimator is used to check (a) roughness (b) flatness (c) angle (d) automobile balance 1.16 Failure of a bead weld between a heavy steel section and a thin section is mainly due to the formation of (a) spheroidite (b) bainite (c) carbon free zone due to burning of carbon at high temperature (d) martensite. 1.17 Ideal surface roughness, as measured by the maximum height of unevenness, is best achieved when the material is removed by (a) an end mill (b) a grinding wheel (c) a tool with zero nose radius (d) a ball mill 1.18 In the specification of dimensions and fits, (a) allowance is equal to bilateral tolerance (b) allowance is equal to unilateral tolerance (c) allowance is independent of tolerance (d) allowance is equal to the difference between maximum and minimum dimension specified by the tolerance. 1.19. In machining using abrasive material, increasing abrasive grain size (a) increases the material removal rate (b) decreases the material removal rate (c) first decreases and then increases the material removal rate (d) first increases and then decreases the material removal rate 1.20. With increasing temperature of intake air, IC engine efficiency (a) decreases (b) increases (c) remains same (d) depends on other factors 1.21. Chills are used in moulds to (a) achieve directional solidification (b) reduce the possibility of blowholes (c) reduce freezing time (d) smoothen metal flow for reducing splatter. GATE ME - 1998 1.22. One of the following statements about PRS (Periodic Reordering System) is not true. Identify, (a) PRS requires continuous monitoring of inventory levels (b) PRS is useful in control of perishable items (c) PRS provides basis for adjustments to account for variations in demand (d) In PRS, inventory holding costs are higher than in Fixed Recorder Quantity System 1.23. In inventory planning, extra inventory is unnecessarily carried to the end of the planning period when using one of the following lot size decision policies: (a) Lot – for – lot production (b) Economic Order Quantity (EOQ) lot size (c) Period Order Quantity (POQ) lot size (d) Part Period total cost balancing 1.24. In a weaving operation, the parameter to be controlled is the number of defects per 10 square yards of material. Control chart appropriate for this task is (a) P - chart (b) C - chart (c) R - chart (d) X -Chart 1.25 Which one of the following forecasting techniques is not suited for making forecasts for planning production schedules in the short range? (a) Moving average (b) Exponential moving average (c) Regression analysis (d) Delphi 2. This question consists of TWENTY-FIVE sub-questions (2.1 – 2.25) of TWO marks each. For each of these sub-questions, four possible alternatives (A, B, C and D) are given, out of which ONLY ONE is correct. 2.1 The general solution of the differential equation 2 2 2 0 d y dy x x y dx dx - + = is: (a) 2 Ax Bx + (A,B are constants) (b) log Ax B x + (A,B are constants) (c) 2 log Ax Bx x + (A,B are constants) (d) log Ax Bx x + (A,B are constants) 2.2. The best fit line using least squares for the data (0,0), (10, 24), (20, 36) and (30,60) is: (a) 2x – y = 0 (b) 2x – y + 4 = 0 (c) 2x – y – 4 = 0 (d) None of these GATE ME - 1998 2.3. The maximum principal strain in a thin cylindrical tank, having a radius of 25 cm and wall thickness of 5 mm when subjected to an internal pressure of 1 MPa, is (taking Young’s modulus as 200 GPa and Poisson’s ratio as 0.2) (a) 4 2.25 10 - × (b) 2.25 (c) 6 2.25 10 - × (d) 22.5 2.4. A square bar of side 4 cm and length 100 cm is subjected to an axial load P. the same bar is then used as a cantilever beam and subjected to an end load P. the ratio of the strain energies, stored in the bar is the second case to that stored in the first case, is: (a) 16 (b) 400 (c) 1000 (d) 2500 2.5. An IC engine has a bore and stroke of 2 units each. The area to calculate heat loss can be taken as (a) 4p (b) 5p (c) 6p (d) 8p 2.6. An air breathing aircraft is flying at an altitude where the air density is half the value at ground level. With reference to the ground level, the air-fuel ratio at this altitude will be (a) 3 2 (b) 2 (c) 2 (d) 4 2.7. For the data listed below for two journal bearings A and B, predict the flow conditions in the bearings Bearing Diameter (m) Radial clearance (m) Surface speed of shaft (m/s) Viscosity of lubricant (Pa – s) Density of lubricant (kg/m 3 ) A 0.01 10 -5 210 0.001 1000 B 0.05 10 -4 10 0.01 850 (a) laminar in both A and B (b) turbulent in both A and B (c) Laminar in A and turbulent in B (d) turbulent in A and laminar B 2.8. The isentropic heat drop in the nozzle of an impulse steam turbine with a nozzle efficiency 0.9, blade velocity ratio 0.5, and mean blade velocity 150 m/s in kJ/kg is (a) 50 (b) 40 (c) 60 (d) 75 2.9. Air ( ) P C 1 / , 1.4 kJ kg ? = = enters a compressor at a temperature of 27°C. the compressor pressure ratio is 4. Assuming an efficiency of 80%, the compressor work required in kJ/kg is (a) 160 (b) 172 (c) 182 (d) 225Read More
380 docs|127 tests
|