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
An aluminium rod of Young's modulus 7.0 x 109 N/m2 has a breaking strain of 0.2%. The minimum cross-sectional area of the rod in m2 in order to support a load of 104 newton is :
1.0 x 10-2
1.0 x 10-3
1.4 x 10-2
7.1 x 10-4
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%?
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
The volume of a solid rubber ball when it is carried from the surface to the bottom of a 200 m deep lake decreases by 0.1%. The value for bulk modulus of elasticity for rubber will be :
2 x 109 pascal
2 x 106 pascal
2 x 104 pascal
2 x 107 pascal
For the same cross-sectional area and for a given load, teh ratio of depressions for the beam of a square cross-section and circular cross-section is :
3 : π
π : 3
1 : 1
1 : π
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)
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 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
A force of 200 N is applied at one end of a wire of length 2 m and having area of cross-section 10-2 cm2. The other end of the wire is rigidly fixed. It coefficient of linear expansion of the wire α = 8 x 10-6/oC and Young's modulus Y = 2.2 x 1011 N/m2 and its temperature is increased by 5oC, then the increase in the tension of the wire will be :
2.4 N
8.8 N
4.2 N
4.4 N