Mechanical Engineering Answers

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

A refrigerator room has a wall 6m long and 3m high. The wall is built of 120mm thick brick, insulated on the inside with an 80mm layer of cork faced with a thin metal sheet. The coefficient of thermal conductivity of the brick is 1.15W/mK while that of the cork is 0.043W/mK. The exterior brick surface temperature of the wall is 21 degrees Celcius and that of the interior metal faced surface is -4d egrees Celcius throughout. Estimate the heat leakage through the wall in 24 hours and also the temperature of the interface between the cork and brick. 

1. A composite wall is made up of two layers of bricks each 100 mm thick with a 50 mm air space between them. The coefficients of thermal conductivity are
2. Inside brick - 0.6 W/m K
3. Air - 0.025 W/m K
4. Outside brick - 0.8 W/m K
5. The wall is 6.15 m long and 5.5 m high.
6. a. Determine the heat loss per hour through the wall if the inside face temperature is 24^oC and the outside face temperature is 7^oC
7. b. Determine the interface temperatures

3. Find the angle of the largest right circular cone which can be inscribed in a sphere of

radius 9 inches.

4. A statue 10 feet high is standing on a base 13 feet high. If an observer’s eye is 5 feet

above the ground, how far should he stand from the base in order that the angle

between his lines of sight to the top and bottom of the statue is a maximum. (How far

should he stand to get the best view of the statue.

5. A steel girder 27 feet long is to be moved on rollers along a passageway 8 feet in

width and into a corridor at right angles to the passageway. If the horizontal width of

the girder is neglected, how wide must the corridor be in order that the girder can go

around the corner?