TOP 10 MCQ STRENGTH OF MATRIAL

 

1.Two bars of different materials are of the same size and are subjected to same tensile forces. If the bars have unit elongations in the ratio of 4 : 7, then the ratio of moduli of elasticity of the two materials is

a)7:4

b)4:7

c)4:17

d) 16 :49

2. If a point in a strained material is subjected to equal normal and tangential stresses, then the angle of obliquity is

a)0

b)45

c)tan 1/2

d)tan2

 3. A flat carrying a pull of 69C kN is con-nected to a gusset plate using rivets. If the pulls required to shear the rivet, to crush the rivet and to tear the plate per pitch length are 68.5 kN, 46 kN and 69 kN respectively, then the number of rivets required is

a)10

b)12

c)15

d)20

 4.The Young's modulus of a wire is defined as the stress which will increase the length of wire compared to its original length

a)half

b)same amount

c)double

d) one-fourth

5. .Percentage reduction of area in performing tensile test on cast iron may be of the order of

a)50%

b)25%

c)0%

d) 15%

6. During a tensile test on a specimen of 1 cm cross-section, maximum load observed was 8 tonnes and area of cross-section at neck was 0.5 cm2. Ultimate tensile strength of specimen is

a)4 tonnes/cm2

b)8 tonnes/cm2

c)16 tonnes/cm2

d) 22 tonnes/cm2

7. The change in the unit volume of a material under tension with increase in its Poisson's ratio will ,

a)increase

b)decrease

c)remain same

d) increase initially and then decrease

8. The stress developed in a material at breaking point in extension is called

a)breaking stress

b)fracture stress

c)yield point stress

d) ultimate tensile stress

9. Curvature of the beam is __________ to bending moment.

a)Equal

b) Directly proportion

c)Inversely proportion

d) Coincides