Elastic Behaviour of Solids

Which term is not related to the elasticity.

Resistance to elastic deformation of a material is measured by:

Out of the following whose elasticity is independent of temperature;

Which of the following statement is incorrect?

If $E_{\mathrm{\theta }}\mathrm{ }\mathrm{a}\mathrm{n}\mathrm{d}\mathrm{ }{\mathrm{E}}_{\mathrm{\varphi }}$ denote the isothermal and adiabatic elasticities respectively of a gas, then $\frac{E_{\mathrm{\theta }}}{{\mathrm{E}}_{\mathrm{\varphi }}}$

Which of the following substance has the highest elasticity?

Two wires, one made of copper and other of steel are joined end to end (as shown in figure). The area of cross section of copper wire is twice that of steel wire. They are placed under compressive force of magnitudes $\mathrm{F}$ . Find the ratio of their lengths such that change in lengths of both wires are same (${\mathrm{Y}}_{\text{S}}=2\times {10}^{11}N {\text{m}}^{-2}$ and ${\mathrm{Y}}_{\text{C}}=\text{1.1}\times {10}^{11}N {\text{m}}^{-2}$)

One end of wire $2 \mathrm{m}$long and diameter$2 \mathrm{mm}$ is fixed in a ceiling. A naughty boy of mass $10 \mathrm{kg}$  jumps to catch the free end and stays there. The change in length of wire is [Take $g=10 m{\mathrm{s}}^{-2}, Y=2\times {10}^{11} N{\mathrm{m}}^{-2}$]