Mechanical Engineering Answers

farmer is using a tandem disk harrow for primary tillage in a medium texture soil. The disk width is 6 m, the travel speed is 10 km, and the tillage depth is 20 cm. Estimate the drawbar power of a tractor required. Ignore any losses that occur during field operations

A circular shaft of 12 cm dia. is subjected to combined bending and twisting moments. The bending moment being three times the twisting moment. If the direct tensile yield point of material is 350 MN/m² and factor of safety on yield is 4, find the allowable twisting moment by     

a) Maximum principal stress theory

b) Maximum shear stress theory

At a point in a strained material, the intensities of normal stresses on two planes at right angles to each other are 35 N/mm² and 20 N/ mm² both tensile. They are accompanied by shear stress of 15 N/ mm². Find the principal planes and principal stresses. Find also maximum shear stress.

A rolled steel Joist of I-Section has flange length of 300 mm. wide and 20 mm thick with a web thickness of 20 mm. and overall depth of I-Section is 600 mm. If this beam carries a UDL of 40 KN/m over the simply supported beam of span 10 m, find the maximum stress produced in the beam.                                                                                             

A canned food product is thermally processed at 125 ° C; the coldest point presents the following values: fh = 40 min, jh = 0.8, jc = 0.8, Initial of the product = 24 ° C and CUT = 8 min. The deteriorating microorganism has a D121 = 1 min and z = 14 ° C. An acceptable spoilage rate has been established as one can for every million cans processed. If the initial microbial population is 106 microorganisms per can, determine:

a) The g value

b) The process time

In how many ways a relation can be represented? State two different

examples to represent each of them.

What is nested Quantifier? Is order important for nested quantifier?

Explain your answer with appropriate example.

How the following products are manufactured.

1. Seemless Tubes

2. Steam Turbines

3. Glass Sheets

A steam pipe 100mm external diameter is to be lagged with two layers of different lagging material each 25mm each material A has a coefficient of thermal conductivity of 0.052W/mk while that of material B is 0.086W/mk Determine which of the two lagging materials must be on the inside to produce the best insulation arrangement if the internal surface temperature is 320°c and the external surface temperature is 20°c Determine the heat loss/h a 10m run of lagged pipe with the best lagging arrangement

steel pipe 150mm external diameter conveys steam at a temperature of 260 degrees and is covered by two layers of lagging, each 50mm thick. The thermal conductivity coefficient of the inside layer of lagging is 0.086W/m.K while that of the outside layer is 0.055W/m.K. The outside surface temperature of the steel pipe can be taken as the same as the temperature of the system. The ambient temperature is 27 degrees. Calculate the heat lost per hour for pipe length 30m. Calculate the interface temperature between the two layers of lagging