 ### Strength of Materials Objective Questions

As compared to uniaxial tension or compression, the strain energy stored in bending is only

• A. 1/8
• B. 1/4
• C. 1/3
• D. 1/2

The ratio of strengths of solid to hollow shafts, both having outside diameter D and hollow having inside diameter D/2, in torsion, is

• A. 1/4
• B. 1/2
• C. 1/16
• D. 15/16
• E. 3/8

The weakest section of a diamond riveting, is the section which passes through

• A. first row
• B. second row
• C. central raw
• D. one rivet hole of end row.

In a loaded beam, the point of con-traflexture occurs at a section where

• A. bending moment is minimum
• B. bending moment is zero or changes sign
• C. bending moment is maximum
• D. shearing force is maximum
• E. shearing force is minimum.

The ratio of elongations of a conical bar due to its own weight and that of a prismatic bar of the
same length, is

• A. 1/2
• B. 1/3
• C. 1/4
• D. 1/5
• E. 1/6

A three-hinged arch is said to be :

• A. statically determinate structure
• B. statically indeterminate structure
• C. a bent beam
• D. none of these.

The shape of the bending moment diagram over the length of a beam, having no external load, is
always

• A. linear
• B. parabolic
• C. cubical
• D. circular.

Pick up the incorrect statement

• A. The cross-sectional area of the welded member is effective
• B. A welded joint develops strength of its parent metal
• C. Welded joints provide rigidity
• D. Welded joints have better finish
• E. Welding takes more time than riveting.

If two forces acting at a joint are not along the straight line, then for the equilibrium of the joint

• A. one of the forces must be zero
• B. each force must be zero
• C. forces must be equal and of the same sign
• D. forces must be equal in magnitude but opposite in sign.

If the shear force along a section of a beam is zero, the bending moment at the section is

• A. zero
• B. maximum
• C. minimum
• D. average of maximum-minimum
• E. None of these.

The shape of the bending moment diagram over the length of a beam, carrying a uniformly

• A. linear
• B. parabolic
• C. cubical
• D. Circular

The minimum number of rivets for the connection of a gusset plate, is

• A. 1
• B. 2
• C. 3
• D. 4

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
• E. 500

A rectangular beam 20 cm wide is subjected to a maximum shearing force of 10, 000 kg, the
corresponding maximum shearing stress being 30 kg/cm2

The depth of the beam is

• A. 15 cm
• B. 20 cm
• C. 25 cm
• D. 30 cm.

The maximum twisting moment a shaft can resist, is the product of the permissible shear stress
and

• A. moment of inertia
• B. polar moment of inertia
• C. polar modulus
• D. modulus of rigidly.

For a simply supported beam with a central load, the bending moment is

• A. least at the centre
• B. least at the supports
• C. maximum at the supports
• D. maximum at the centre.

The deflection of any rectangular beam simply supported, is

• A. directly proportional to its weight
• B. inversely proportional to its width
• C. inversely proportional to the cube of its depth
• D. directly proportional to the cube of its length
• E. none of these. 