Q. Steam in the condenser of a thermal power plant is to be condensed at a temperature of 30°C with cooling water which enters the tubes of the condenser at 14°C and exits at 22°C. The total surface area of the tubes is 50 m2, and the overall heat transfer coefficient is 2000 W/m2 K. The heat ...

Q. A welding operation is being performed with voltage = 30 V and current = 100 A. The cross-sectional area of the weld bead is 20 mm2. The work-piece and filler are of titanium for which the specific energy of melting is 14 J/mm3. Assuming a thermal efficiency of the welding process 70%, the ...

Q. A circular hole of 25 mm diameter and depth of 20 mm is machined by EDM process. The material removal rate (in mm3/min) is expressed as 4 ´104 IT -1.23 where I = 300 A and the melting point of the material, T = 1600°C . The time (in minutes) for machining this hole is  Ans: 7.00 - 7.30 ...

Q. The arc lengths of a directed graph of a project are as shown in the figure. The shortest path length from node 1 to node 6 is Ans: 7 Sol:

Q. For sand-casting a steel rectangular plate with dimensions 80 mm × 120 mm × 20 mm, a cylindrical riser has to be designed. The height of the riser is equal to its diameter. The total solidification time for the casting is 2 minutes. In Chvorinov’s law for the estimation of the total ...

Q. Taylor’s tool life equation is used to estimate the life of a batch of identical HSS twist drills by drilling through holes at constant feed in 20 mm thick mild steel plates. In test 1, a drill lasted 300 holes at 150 rpm while in test 2, another drill lasted 200 holes at 300 rpm. The maximum ...

Q. Following data correspond to an orthogonal turning of a 100 mm diameter rod on a lathe. Rake angle: +15o ; Uncut chip thickness: 0.5 mm; nominal chip thickness after the cut: 1.25 mm. The shear angle (in degrees) for this process is ______________(correct to two decimal places). Ans:

Q. The true stress (in MPa) versus true strain relationship for a metal is given by σ = 1020e 0.4  The cross-sectional area at the start of a test (when the stress and strain values are equal to zero) is 100 mm2. The cross-sectional area at the time of necking (in mm2) is ...

Q. A test is conducted on a one-fifth scale model of a Francis turbine under a head of 2 m and volumetric flow rate of 1 m3/s at 450 rpm. Take the water density and the acceleration due to gravity as 103 kg/m3 and 10 m/s2, respectively. Assume no losses both in model and prototype turbines. The ...

Q. Ambient air is at a pressure of 100 kPa, dry bulb temperature of 30 oC and 60% relative humidity. The saturation pressure of water at 30 oC is 4.24 kPa. The specific humidity of air (in g/kg of dry air) is_______(correct to two decimal places). Ans: 16.00 - 16.50