A metal block is experiencing 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
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%
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
Young's modulus of the material of a wire of length L and radius r is Y N/m2. If the length is reduced to L/2 and radius to r/2, the Young's modulus will be :
Y/4
Y/2
Y
2Y
A 5 m long steel wire is suspended from the ceiling of a room. A sphere of mass 25 kg and 10 cm radius is attached to another end of the wire. The height of the ceiling is 5.21 m. When the sphere is made to oscillate as a pendulum, then its lowest point just touches the floor. The velocity of the sphere at the lowest point will be :
(Given : Y = 2 x 1011N/m2, radius of wire = 0.05 cm)
3.71 m/s
3.71 cm/s
37.1 cm/s
37.1 m/s
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
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
A steel wire of uniform cross-section of 2 mm2 is heated upto 50oC and clamped rigidly at two ends. If the temperature of wire falls to 30oC then change in tension in the wire will be :
(Given : Coefficient of linear expansion of steel is 1.1 x 10-5°C and Young's modulus of elasticity of steel is 2 x 1011N/m2)
A wire of density 9 gm/cm3 is stretched and clamped between two clamps distant 100 cm apart by a force which produces an elongation of 0.05 cm in it. If Y = 9 x 1011 dyne/cm2 then the minimum frequency of transverse vibrations will be :
15.15 per sec
25.25 per sec
35.35 per sec
53.53 per sec
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
