Download PTU (Punjab Technical University) B.Tech (Bachelor of Technology) / BE (Bachelor of Engineering) 2021 January Automation-And-Robotics 3rd Sem 76501 Strength Of Materials Previous Question Paper
Roll No.
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech.(Automation & Robotics) (2018 Batch) (Sem.?3)
STRENGTH OF MATERIALS
Subject Code : BTAR-302-18
M.Code : 76501
Time : 3 Hrs. Max. Marks : 60
INST RUCT IONS T O CANDIDAT ES :
1 .
SECT ION-A is COMPULSORY cons is ting of TEN questions carrying TWO marks
each.
2 .
SECT ION-B c ontains F IVE questions c arrying FIVE marks eac h and s tud ents
have to atte mpt any FOUR q ues tions.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt any T WO questio ns.
SECTION-A
Write briefly :
1.
Distinguish between longitudinal and transverse strain.
2.
Define modulus of rigidity and bulk modulus.
3.
Give the classification of beams.
4.
Define point of contraflexure.
5.
Distinguish between moment of inertia and polar moment of inertia.
6.
Define bending stress and write its units.
7.
Define stiffness of close coiled helical spring and write its formula.
8.
Distinguish between thin and thick cylinders.
9.
Write the formula to find power transmitted by shaft.
10. What do you mean by build up cylindrical shells?
1 | M-76501
(S2)- 436
SECTION-B
11. A square steel rod 20 mm ? 20 mm in section is to carry an axial compressive load of
100 kN. Calculate the shortening in a length of 50 mm. E = 2.14 ? 106 kN/m2.
12. Explain the procedure to construct Mohr's circle for a body subjected to two
perpendicular direct stresses.
13. A simply supported beam of 10 m span carries the concentrated loads of 4 kN, 5 kN and
3 kN at distances 3, 7 and 11m respectively from one end. Draw shearing force and
bending moment diagrams.
14. A timber beam 150 mm ? 250 mm in cross-section is simply supported at its ends and
has a span of 3.5 m. The maximum safe allowable stress in bending is 7500 k N/m2. Find
the maximum safe uniformly distributed load which the beam can carry. What is the
maximum shear stress in the beam for the UDL calculated?
15. A simply supported beam is having length L and it carries a point load W at its mid span.
Derive the formulae to find maximum deflection and maximum slope using double
integration method.
SECTION-C
16. A hollow shaft, having an inside diameter 60% of its outer diameter is to replace a solid
shaft transmitting the same power at the same speed. Calculate the percentage saving in
material, if the material to be used is also the same.
17. A boiler shell is to be made of 15 mm thick plate having tensile stress of 120 M N/m2. If
the efficiencies of the longitudinal and circumferential joints are 70% and 30%
respectively, determine :
a) Maximum permissible diameter of the shell for an internal pressure of 2 M N/m2, and
b) Permissible intensity of internal pressure when the shell diameter is 1.5 m.
18. a) Explain theorem of perpendicular axes to find moment of inertia.
b) Write a note on Maxwell's reciprocal theorem.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
2 | M-76501
(S2)- 436
This post was last modified on 26 June 2021