Columns & Struts (SOM/TOS-I) MCQs

Subject:- Strength of Material (SOM) 

Topic:- Columns & Struts (SOM)

1. The materials which have the same elastic properties in all directions, are called

(A) isotropic

(B) brittle

(C) homogeneous

(D) hard

Answer: A

2. The slenderness ratio of a vertical column of a square cross-section of 2.5 cm sides and 300 cm length, is

(A) 200

(B) 240

(C) 360

(D) 416

Answer: D

3. The region of the cross-section of a column in which compressive load may be applied without producing any tensile stress, is known as the core of the cross-section. In circular columns the radius of the core, is

(A) one-half of the radius

(B) one-third of the radius

(C) one-quarter of the radius

(D) one-fifth of the radius

Answer: C

4. The radius of gyration of a squar section is not proportional to

(A) square root of the moment of inertia

(B) square root of the inverse of the area

(C) square root of the moment of inertia divided by area of the section

(D) side of squar

Answer: D

5. The length of a column, having a uniform circular cross-section of 7.5 cm diameter and whose ends are hinged, is 5 m. If the value of E for the material is 2100 kN/cm2, the permissible maximum crippling load will be

(A) 1.288 kN

(B) 12.88 kN

(C) 128.8 kN

(D) 288.0 kN

Answer: B

6. Struts are load carrying members of a frame structure which are subjected to

(A) axial tension loads

(B) axial compressive loads

(C) torsional loads

(D) transverse loads

Answer: B

7. The greatest eccentricity which a load W can have without producing tension on the cross-section of a short column of external diameter D and internal diameter d, is

(A) 4W / π(D2-d2)

(B) π(D4-d4)/32D

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(C) (D2+d2)/8D

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(D) (D2-d2)/8D

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Answer: C

8. Euler's formula states that the buckling load P for a column of length l, both ends hinged and whose least moment of inertia and modulus of elasticity of the material of the column are I and E respectively, is given by the relation

(A) P=π2EI/L2

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(B) P=πL2/EI

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(C) P=πEI/L2

$\frac{{\mathrm{}}^{}}{}$

(D) P=π2EI/L3

$\frac{{\mathrm{}}^{}}{}$

Answer: A

9. Rankine-Golden formula accounts for direct as well as buckling stress and is applicable to

(A) very long columns

(B) long columns

(C) short columns

(D) intermediate columns

Answer: D

10. Maximum deflection of a cantilever due to pure bending moment M at its free end, is

(A) ML2/3EI

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(B) ML2/4EI

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(C) ML2/6EI

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(D) ML2/2EI

$\frac{}{}$

Answer: D

11. The ratio of the effective length of a column and minimum radius of gyration of its cross-sectional area, is known

(A) buckling factor

(B) slenderness ratio

(C) crippling factor

(D) none of these

Answer: B

12. A long vertical member, subjected to an axial compressive load, is called

(A) a column

(B) a strut

(C) a tie

(D) a stanchion

Answer: A

13. Columns of given length, cross-section and material have different values of buckling loads for different end conditions. The strongest column is one whose

(A) one end is fixed and other end is hinged

(B) both ends are hinged or pin jointed

(C) one end is fixed and the other end entirely free

(D) both the ends are fixed

Answer: D

14. The slenderness ratio of a vertical column of square cross- section of 10 cm side and 500 cm long, is

(A) 117.2

(B) 17.3

(C) 173.2

(D) 137.2

Answer: C

15. The equivalent length of a column fixed at one end and free at the other end, is

(A) 0.5L

(B) 0.7L

(C) L

(D) 2L

Answer: D

16. The equivalent length of a column fixed at both ends, is

(A) 0.5L

(B) 0.7L

(C) L

(D) 2L

Answer: A

17. A column is said to be of medium size if its slenderness ratio is between

(A) 20 and 32

(B) 32 and 120

(C) 120 and 160

(D) 160 and 180

Answer: B

18. The radius of gyration of a section of area A and least moment of inertia I about the centroidal axis, is

(A) root(A/I)

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(B) (I/A)

$\frac{}{}$

(C) root(I/A)

$\sqrt{\frac{}{}}$

(D) (A/I)

$\sqrt{\frac{{\displaystyle }}{}}$

Answer: C

19. The equivalent length of a column of length L, having both the ends hinged, is

(A) 2L

(B) L

(C) 0.5L

(D) 0.7L

Answer: B

20. P=π2EI/L2 is the equation for Euler's crippling load if

(A) both the ends are fixed

(B) both the ends are hinged

(C) one end is fixed and other end is free

(D) one end is fixed and other end is hinged

Answer: B

21. P=π2EI/4L2 is the equation of Euler's crippling load, if

(A) both the ends are fixed

(B) both the ends are hinged

(C) one end is fixed and other end is free

(D) one end is fixed and other end is hinged

Answer: C

22. The equivalent length is of a column of length L having both the ends fixed, is

(A) 2L

(B) L

(C) L/2

(D) 0.7L

Answer: C

23. The ratio of crippling loads of a column having both the ends fixed to the column having both the ends hinged, is

(A) 1

(B) 2

(C) 3

(D) 4

Answer: D

24. Pick up the correct statement from the following:

(A) The structural member subjected to compression and whose dimensions are small as compared to its length, is called a statement

(B) The vertical compression members, are generally known as columns or stanchions

(C) Deflection in lateral direction of a long column, is generally known as buckling

(D) All the above

Answer: D

25. Slenderness ratio of a long column, is

(A) area of cross-section divided by radius of gyration

(B) area of cross-section divided by least radius of gyration

(C) radius of gyration divided by area of cross-section

(D) length of column divided by least radius of gyration

Answer: D

26. P=4π2EI/L2 is the equation of Euler's crippling load if

(A) both the ends are fixed

(B) both the ends are hinged

(C) one end is fixed and other end is free

(D) one end is fixed and other end is hinged

Answer: A

27. The equivalent length of a column of length L, having one end fixed and other end hinged, is

(A) 2L

(B) L

(C) L/2

(D) 0.707L

Answer: D

28. The equivalent length of a column of length L having one end fixed and the other end free, is

(A) 2L

(B) L

(C) L/2

(D) 0.707L

Answer: A

29. The radius of gyration of a rectangular section (depth D, width B) from a centroidal axis parallel to the width is

(A) D/2

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(B) D/root(3)

$\frac{\sqrt{\mathrm{}}}{}$

(C) D/2root(3)

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(D) D/4root(3)

Answer: C

30. As per the Euler's theory, failure in column will be by

(A) Buckling

(B) Crushing

(C) Crippling

(D) Crippling and buckling

Answer: A

31. Euler’s formula for mild steel column is not applicable if slenderness ratio is less than

(A) 80

(B) 160

(C) 240

(D) 320

Answer: A

32. Euler’s Crippling load of a square column cross section will be _____ if its side is doubled

(A) 2 times

(B) 1/2 times

(C) 16 times

(D) 1/4 times

Answer: C

33. Euler’s column theory is applicable only if _____ stress are negligible in comparison to _____ stress

(A) Bending, axial

(B) Axial, bending

(C) Shear, bending

(D) Axial, shear

Answer: B

34. A rectangular column has dimensions B x D (whereD > B) and different end conditions in both directions. The column will buckle in the direction

(A) In which slenderness ratio is larger

(B) In which slenderness ratio is smaller

(C) of B

(D) of D

Answer: A

35. Factor of safety and safety factors are _____

(A) Same

(B) Different

(C) Equal

(D) None

Answer: B

36. A column is having initial curvature and is loaded by axial load. The axial load carrying capacity of column _____ due to initial curvature

(A) Increase

(B) Remains same

(C) Decreases

(D) Depends on modulus of elasticity

Answer: C

37. The formula which can be used for column load to account combined effect of bending and direct stresses is

(A) Perry's formula

(B) Euler's formula

(C) Rankine's formula

(D) Straight line formula

Answer: A

38. Euler's theory is applicable for

(A) Short column

(B) Any column

(C) Long column

(D) Intermediate column

Answer: C

39. Euler's theory is applicable when

(A) Column is initially straight

(B) Self weight of column is accounted in analysis

(C) Column fails by crushing

(D) Cross section is non-prismatic

Answer: A

40. "If a column has length pie m, its Young’s modulus is 200GPa and moment of inertia 1000000 mm4 and is hinged at both ends. The Euler’s load shall be"

(A) 100000N

(B) 200000N

(C) 400000N

(D) 20000N

Answer: B

41. Struts are load currying members of a truss structure which are subjected to

(A) Axial tensile loads

(B) Axial compressive loads

(C) Torsional loads

(D) Transverse loads

$\frac{\mathrm{}}{}$

Answer: B