Q. A vehicle powered by a spark ignition engine follows air standard Otto cycle (g=1.4). The engine generates 70 kW while consuming 10.3 kg/hr of fuel. The calorific value of fuel is 44,000 kJ/kg. The compression ratio is _________ (correct to two decimal places). Ans: 7.40 – 7.80
A vehicle powered by a spark ignition engine follows air standard Otto cycle (g=1.4) Read More »
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.
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 welding
A welding operation is being performed with voltage = 30 V and current = 100 A Read More »
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:
A circular hole of 25 mm diameter and depth of 20 mm is machined by EDM process Read More »
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:
The arc lengths of a directed graph of a project are as shown in the figure Read More »
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 solidification time,
For sand-casting a steel rectangular plate with dimensions 80 mm × 120 mm × 20 mm Read More »
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
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:
Following data correspond to an orthogonal turning of a 100 mm diameter rod on a lathe Read More »
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 ________________(correct to two decimal places)
The true stress (in MPa) versus true strain relationship for a metal is given by Read More »
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
