A bridge can bear 4 x 104 kg weight. If the breaking stress is 47 x 103 N/m3 and factor of safety is 5 then the area of cross section of the rod will be :
4.34 m2
43.4 m2
0.434 m2
0.04 m2
A thick rope of density 'ρ' and length 'L' is hung from a rigid support. The Young's modulus of the material of rope is 'Y'. The increase in length of the rope due to its own weight is :
1/4 ρgL2/Y
1/2 ρgL2/Y
ρ gL2/Y
ρ gL/Y
The bulk modulus of rubber is 9 x 108 N/m2. To what depth below the surface of sea should the rubber ball taken as to decrease its volume by 0.1%?
1 m
10 m
100 m
1 km
The magnitude of the force developed by raising the temperature from 0oC to 100oC of the iron bar 1.00 m long and 1 cm2 cross-section when it is held so that it is not permitted to expand or bend is :
(Given : α = 10-5 /oC and Y = 1011 N/m2)
103 N
104 N
105 N
109 N
The Young's modulus of a wire is Y. If the energy per unit volume is E, then the strain will be :
EY
E/Y
The Poisson's ratio for a material is 0.1. If the longitudinal strain of a rod of this material is 1 x 10-3, then the percentage change in the volume of rod will be :
8%
0.8%
0.08%
0.008%
The length of an iron wire is L and area of cross-section is A. The increase in length is l on applying the force F on its two ends. Which of the statement is correct ?
Increase in length is inversely proportional to A
Increase in length is proportional to Young's modulus
Increase in length is inversely proportional to its length L
Increase in length is proportional to area of cross-section A
A metal block is experencing an atmospheric pressure of 105 N/m2. When the same block is placed in a vaccum chamber, the fractional change in its volume : (the bulk modulus of metal is 1.25 x 1011 N/m2)
8 x 10-7
1 x 10-7
4 x 10-7
2 x 10-7
A uniform elastic plank moves due to a constant force F placed over a smooth surface. The area of end face is S and Young's modulus of the material is E. What is the average strain produced in the direction of the force?
F/4SE
Zero
F/SE
F/2SE
