A metal rod has length, cross-sectional area and Young's modulus as $L, A$ and $Y$, respectively. If the elongation in the rod produced is I, then work done is proportional to

Two wires of different materials have same length $$L$$ and same diameter $$d$$. The second wire is connected at the end of the first wire and forms one single wire of double the length. This wire is subjected to stretching force $$F$$ to produce the elongation I. The two wires have

Two wires $$A$$ and $$B$$ are stretched by the same load. The radius of wire $$A$$ is double the radius of wire $$B$$. The stress on the wire $$B$$ as compared to the stress on the wire $$A$$ is

The density of a metal at normal pressure $$p$$ is $$\rho$$. When it is subjected to an excess pressure, the density becomes $$\rho^{\prime}$$. If $$K$$ is the bulk modulus of the metal, then the ratio $$\frac{\rho^{\prime}}{\rho}$$ is