421. In the torsion equation the term J/R is called
shear modulus
section modulus
polar modulus
none of these
✅ The correct answer is option C.
Strength of Materials MCQs
422. The torque transmitted by a solid shaft of diameter (D) is (where τ = Maximum allowable shear stress)
x τ x D3
x τ x D3
x τ x D3
x τ x D3
✅ The correct answer is option B.
423. Two closely coiled helical springs ‘A’ and ‘B’ are equal in all respects but the number of turns of spring ‘A’ is half that of spring ‘B’ The ratio of deflections in spring ‘A’ to spring ‘B’ is
1-Aug
1-Apr
1-Feb
2
✅ The correct answer is option C.
424. Two shafts ‘A’ and ‘B’ transmit the same power. The speed of shaft ‘A’ is 250 r.p.m. and that of shaft ‘B’ is 300 r.p.m. The shaft ‘B’ has the greater diameter.
TRUE
FALSE
✅ The correct answer is option B.
425. The point of contraflexure is a point where
shear force changes sign
bending moment changes sign
shear force is maximum
bending moment is maximum
✅ The correct answer is option B.
426. In order to know whether a column is long or short, we must know its slenderness ratio.
TRUE
FALSE
✅ The correct answer is option A.
427. When two main plates are kept in alignment butting each other and riveted with cover plate on both sides of the main plates with two rows of rivets in each main plate, the joint is known as __________ double cover butt joint.
single riveted
double riveted
✅ The correct answer is option B.
428. A steel bar of 5 mm is heated from 15° C to 40° C and it is free to expand. The bar Will induce
no stress
shear stress
tensile stress
compressive stress
✅ The correct answer is option A.
429. The limit of eccentricity is based upon no tension condition.
TRUE
FALSE
✅ The correct answer is option A.
430. If the depth is kept constant for a beam of uniform strength, then its width will vary in proportional to (where M = Bending moment)
M
M
M2
M3
✅ The correct answer is option A.