Question Paper: Design of Machine Elements 1 : Question Paper Jun 2015 - Mechanical Engineering (Semester 5) | Visveswaraya Technological University (VTU)
0

## Design of Machine Elements 1 - Jun 2015

### Mechanical Engg. (Semester 5)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS
(1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks.
1 (a) A shaft as shown in Fig Q1 (a) is subjected to bending land of 3kN, torque of 1×106 N-mm and an axial force of 15kN. Calculate the stresses at 'A' and 'B' (12 marks) 1 (b) What is mechanical engineering design? State steps involved in mechanical engineering design.(4 marks) 1 (c) Explain biaxial and triaxial stresses with neat sketches.(4 marks) 2 (a) State and explain the theories of failure applicable to i) Ductile ii) Brittle materials.(6 marks) 2 (b) What is stress concentration? Explain the factors affecting the stress concentration.(4 marks) 2 (c) A rectangular beam of 100 mm with and 200 mm depth is freely supported over a span of 2m. A load of 10kN is dropped on the middle of beam from a height of 10mm. Find the maximum instantaneous deflection and stress induced in the beam. Take E=2×105 Mpa(10 marks) 3 (a) Explain with the neat sketches the different types of varying stresses.(5 marks) 3 (b) Write a note on S-N diagram.(5 marks) 3 (c) A steel cantilever is 200mm long. It is subjected to an axial load which varies from 150N (compression) to 450N(tension) and a transverse load at its free end which varies from 80N (up) to 120N (down). The cantilever beam is of circular in cross section having a diameter of 2d for the first 50mm and diameter 'd' for the remaining length. Determine its diameter assuming the following:
Factor of safety =
Yield Stress =330 MPa
Endurance limit=300 MPa