List of top General Engineering Questions

A metallic cylindrical pressure vessel, used to store compressed air in a plant, has 1 m mean radius and 4 mm wall thickness. The maximum allowable normal and shear stresses in the cylindrical portion of the vessel are 100 MPa and 40 MPa, respectively. Considering only these data in the design, the maximum allowable internal gauge pressure (in MPa) of the compressed air is ______ . (Rounded off to 2 decimal places)

In a sand mold, a sprue of height \(h_2=200\ mm\) is to be provided for maintaining the molten metal flow rate of \(10^6\ mm^3/s\). The height of liquid column above the point 2 is kept constant at \(h_c=25\ mm\). The cross-sectional areas of the sprue at points 2 and 3 are \(A_2\) and \(A_3\), respectively. The points 1 and 3 are at the atmospheric pressure. Assuming the gauge pressure at point 2 to be zero as the limiting case to prevent aspiration effect, the ratio \(\frac {A_3}{A_2}\) _____ . (Rounded off to 2 decimal places)

A flat belt drive with pulley of r = 20 cm radius is designed to transmit 6.283 kW power at 600 RPM. In the figure, τ is the corresponding torque. If the coefficient of static friction between the belt and the pulley is 0.3, then the minimum value of the tightening force F (in kN) required to prevent the belt slip is _____ . (Rounded off 2 decimal places)

In an air-standard Otto cycle, the pressure and temperature of air just before the compression stroke are 200 kPa and 26.85 °C, respectively. The combustion process is assumed to be a constant volume process, where 1.02 MJ/kg heat is added. The cycle efficiency is 50%. The adiabatic index \(γ\) and specific heat at constant volume \(C_v\) can be considered to be constant during the process (corresponding values taken at the mean cycle temperature).
Assuming that the ideal gas law is applicable, \(γ = \frac 43\) and \(c_v= 0.85\ kJ/kg-K\), the maximum pressure (in MPa) reached during the cycle is _____ . (Rounded off to 1 decimal place)

An irrigation pump is used to draw water from a pond. One end of a 5.05 cm diameter hose pipe is connected to the outlet of the pump at 1.02 m below the surface level, and just after the pump, the static gauge pressure and flow rate of the water are 50 kPa and 8 kg/s, respectively. The pumped water is discharged at the ground level through a nozzle. Assume that the flow through the hose pipe and nozzle is steady and laminar, and frictional and viscous losses are negligible. The density of water is 1000 kg/m3 and the acceleration due to gravity is 9.81 m/s2. If the static pressure at the nose/exit of the nozzle just reduces to atmospheric pressure then the nose diameter (in cm) of the nozzle is _____ . (Rounded off to 2 decimal places)