BIWTA Written Exam Questions for Mechanical Engineers

1. What is “ton of refrigeration”
2. Define boiler mountings  with examples.
3. Define boiler accessories with examples. 
4. Write down the 1^st and 2^nd  law of thermodynamics. 
5. Draw the typical stress-strain diagram of mild steel showing proportional limit, yield strength, ultimate strength and breaking strength on it. 
6. Define modulus of elasticity and modulus of rigidity. For a material which one is greater? 
7. A solid steel shaft in a rolling mill transmits 20 kW at 2 Hz.Determine the diameter of the shaft if the shearing stress in not to exceed 40MPa.  

8. A uniformly distributed load of magnitude w is applied over the whole span of a simply supported beam of length L. Draw the shear force and bending moment diagrams of the beam.

9. A furnace wall of thickness 1 m and of surface area 2 m² is made of a material whose thermal conductivity is 20 W/mK. The temperatures of the inner and outer surfaces of the wall are 1000⁰C and 200⁰C, respectively. Determine the heat flow through the wall.