Question

In plotting stress versus strain curves for two materials P and Q, a student by mistake puts strain on the y-axis and stress on the x-axis as shown in the figure. Then the correct statement(s) is (are)

• A. P has more tensile strength than Q
• B. P is more ductile than Q
• C. P is more brittle than Q
• D. The Young's modulus of P is more than that of Q

Answer 1

Answer: (A), (B)

P is more ductile than Q

For stress on y-axis and strain on x-axis, the slope is given by
$\frac{Stress}{Strain}$=Youngs modulus $\left(E\right)$
Larger the value of E, greater will be its tensile strength.
For the given graph,
$\frac{Strain}{Stress}=\frac{1}{E}$
Since its evident from the graph that slope for P is greater than that of Q.
Hence youngs modulus for Q will be greater than P.
Since for given stress, strain in P is more than that in Q therefore P is more ductile than Q.
The breaking stress of P is more than that of Q, hence P has more tensile strength than Q.