Strength of Material (Part-5) (General Engineering) (SSC JE)

Total Questions: 21

11. If the lines of action of loads on a beam do not pass through shear centre, the beam is subjected [BPSC AE (GEN. ENGG.)-2001 ]

Correct Answer: (d) twisting
Solution:

Shear center–Shear center is the point in or outside a section through which the shear force applied produces only bending.

• If the lines of action of loads on a beam do not pass through shear center, then the beam is subjected twisting.

Property of shear center–
(i) Shear center will be always lie on the axis of symmetry.

(ii) If there is more than one axis of symmetry, it lies at the intersection of symmetrical axes.

12. The moment of inertia of a beam section about a principal axis is [BPSC AE (GEN. ENGG.)-2001 ]

Correct Answer: (d) zero
Solution:

Principal axis of a cross-section are defined as the axis about which product of moment of inertia is zero.

• Principal axis are the main axis of a member which are perpendicular and intersect each other at the center of area or centroid.

Note– Moments of inertia which are always positive and the product of inertia may be either positive, negative or zero depending upon the objects shape and the orientation of the co-ordinate axes.

13. The strain energy in an elastic column of solid circular section of diameter d carrying a given load at the top is U. If the column section is tubular with external diameter d and internal diameter d/2, the strain energy is [BPSC AE (GEN. ENGG.)-2001 ]

Correct Answer: (d) none of these
Solution:

14. At a point in a plate subjected to in-place forces the maximum and the minimum shearing stress at the same point is [BPSC AE (GEN. ENGG.)-2001 ]

Correct Answer: (d) zero
Solution:

15. The maximum shearing stress in simply supported beam of span 4m and of rectangular section 100 mm × 160 mm carrying uniformly distributed load of 8 kN/m is [BPSC AE (GEN. ENGG.)-2001 ]

Correct Answer: (b) 1.5 N/mm²
Solution:

16. If a body is supported by more constraints than required, than it is statically [MPSC AE PRE -09.07.2017]

Correct Answer: (a) indeterminate
Solution:

Statically determinate– A statically determinate structure is the one in which reactions and internal forces can be determined solely from free body diagrams and equation of equilibrium.

Example–Simply supported
Statically indeterminate–When the static equilibrium equations are insufficient to find the reaction forces at the support that system is known as statically indeterminate.
Ex- Two hinged arch

17. The number of independent equations of equilibrium a body subjected to a system of coplanar forces is [BPSC AE (GEN. ENGG.)-2001 ]

Correct Answer: (b) three
Solution:

18. Ultimate strain of mild steel rods is [BPSC AE (GEN. ENGG.) 07.08.2019 ]

Correct Answer: (b) more than TMT rods
Solution:

Ultimate tensile strain of mild steel is 0.12% to 0.2% which is more than TMT bars because TMT bars have low carbon content, which is indicate ductility of TMT bar is higher than mild steel.
• The corrosive resistance property of TMT bar is better than mild steel.
• TMT bar have higher fatigue strength

19. A rectangular beam of width 100 mm is subjected to a maximum shear force of 60 KN. The corresponding maximum shear stress in the cross section is 4N/mm². What is the depth of the beam? [JSSC JE (GEN. ENGG.)-23.10.2022 ]

Correct Answer: (c) 225 mm
Solution:

20. S.I. unit of Strain is ________. [IREL Diploma Trainee-11.09.2022 ]

Correct Answer: (d) No unit
Solution:

Strain–It is defined as the ratio of change in dimension to its original dimension. It is a dimensionless parameter (No unit).
Strain 'ε' = Change in dimension/Original dimension