Mechanical Prop...

Which of the following apparatus is used to determine the Young's modulus of the material of a given wire?

A copper wire of length $$2.4m$$ and a steel wire of length $$1.6m$$, both the diameter $$3mm$$, are connected end to end. The ratio fo elongation of steel to the copper wires is then
$$\left( { Y }_{ copper }=1.2\times { 10 }^{ 11 }N\quad { m }^{ -2 },{ Y }_{ steel }=2\times { 10 }^{ 11 }N\quad { m }^{ -2 } \right) $$

Match the column I with column II

If in the above question, the Young's modulus of the material is Y, the value of extension x is:

A metal wire of length $$L_1$$ and area of cross section A is attached to a rigid support. Another metal wire of length $$L_2$$ and of the same cross-sectional area is attached to the free end of the first wire. A body of mass M is then suspended from the free end of the second wire. If $$Y_1$$ and $$Y_2$$ are the Young's moduli of the wires respectively, the effective force constant of the system of two wires is

A steel bar $$ABCD$$ $$40cm$$ long is made up of three parts $$AB, BC$$ and $$CD$$, as shown in the figure The rod is subjected to a pull of $$25kN$$. The total extension of the rod is (Young's modulus for steel $$2\times { 10 }^{ 11 }N{ m }^{ -2 }$$:

The mean distance between the atoms of iron is $$3\times10^{-10}m$$ and interatomic force constant for iron is $$7 N m^{-1}$$. The Young's modulus of electricity for iron is 

Find the stress developed inside a tooth cavity filled with copper when hot tea at temperature of $$ 57^o C $$ is drunk. (Take temperature of tooth to be $$ 37^o C,\alpha =1.7\times { 10 }^{ -5 }{ }{ /^o C} $$ and bulk modulus for copper $$ =140\times { 10 }^{ 9 }N{ m }^{ -2 } $$ ) 

The adjacent graph shows the extension ($$\Delta l$$) of a wire of length $$1m$$ suspended from the top of a roof at one end and with a load $$W$$ connected to the other end. If the cross-sectional area of the wire is $${ 10 }^{ -6 }{ m }^{ 2 }$$, the Young's modulus of the material of the wire is

The ratio of diameters of two wires of same material is n: 1. The length of  each wire is 4 m. On applying the same load, the increases in the length of the thin wire will be (n > l)