WorksheetsCivil war Day 4(sep 18)-PWD
Total questions: 10
Worksheet time: 10mins
Name
Class
Date
1.
A composite bar is made of Steel & Aluminium strips each having 3 cm² area of cross-section. The composite bar is subjected to an axial load of 12000 N. If E_steel = 3E_Al, the stress in steel is
a)
10 N/mm²
b)
20 N/mm²
c)
30 N/mm²
d)
None of the above
2.
Two bars of different materials and same size are subjected to the same tensile force. If the bars have unit elongation in the ratio of 2:5 then, the ratio of modulus of elasticity of the two materials will
a)
1:5
b)
5:2
c)
1:1
d)
2:5
3.
Two circular bars A and B of same material are subjected to uniaxial loading. If the diameter and load acting on bar B is double than that of A, the ratio of safety of bar B to A is
a)
2
b)
1/2
c)
1/4
d)
4
4.
The Poisson's ratio of a material whose Young's modulus is 1.2 × 10⁵ N/mm² and modulus of rigidity is 4.8 × 10⁴ N/mm², is
a)
2.25
b)
1.25
c)
0.25
d)
0.5
5.
For a given material assume, Young’s modulus E = 300 GN/m² and Modulus of rigidity G = 150 GN/m². Its Bulk modulus K will be
a)
120 GN/m²
b)
100 GN/m²
c)
200 GN/m²
d)
250 GN/m²
6.
If all dimensions of a prismatic bar of square cross section suspended freely from the ceiling of a roof is doubled, the total elongation due to self weight will become
a)
8 times
b)
4 times
c)
2 times
d)
16 times
7.
The ratio of elongation of a conical bar due to its own weight and that of a prismatic bar of same length is
a)
3
b)
1/2
c)
1/3
d)
2
8.
If the external load tries to push the cross section of a bar, it will be under
a)
tensile stress
b)
compressive stress
c)
shear stress
d)
volumetric stress
9.
The change in length due to a tensile or compressive force acting on a body is given by
a)
PA/LE
b)
PL/AE
c)
AE/PL
d)
E/PLA
10.
Material with higher value of coefficient of thermal expansion will be having ...... change in length due to temperature change
a)
less
b)
more
c)
change in length does not depend on value of coefficient of thermal expansion
d)
cannot be predicted
100 %
