Three wires \(A,B,C\) made of the same material and radius have different lengths. The graphs in the figure show the elongation-load variation. The longest wire is:
                    
1. \(A\)
2. \(B\)
3. \(C\)
4. All of the above

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

1. $2\times {10}^{11}N/m^2$

2. $2\times {10}^{-11}N/m^2$

3. $3\times {10}^{-12}N/m^2$

4. $2\times {10}^{-13}N/m^2$

The diagram shows stress v/s strain curve for the materials A and B. From the curves we infer that

1. A is brittle but B is ductile  

2. A is ductile and B is brittle

3. Both A and B are ductile      

4. Both A and B are brittle

The stress versus strain graphs for wires of two materials A and B are as shown in the figure. If $Y_A$ and $Y_B$ are the Young ‘s modulii of the materials, then

1. $Y_B=2Y_A$

2. $Y_A=Y_B$

3. $Y_B=3Y_A$

4. $Y_A=3Y_B$

The stress-strain curves are drawn for two different materials \(X\) and \(Y.\) It is observed that the ultimate strength point and the fracture point are close to each other for material \(X\) but are far apart for material \(Y.\) We can say that the materials \(X\) and \(Y\) are likely to be (respectively):