JEE Physics 2026 Question with Solution

Given: A strain-stress plot for materials A, B, C and D is shown.

Find: Which material has the largest Young's modulus.

Young's modulus is

$$Y = \frac{\text{stress}}{\text{strain}}$$

In a strain-stress graph, the slope is

$$\text{slope} = \frac{\text{strain}}{\text{stress}} = \frac{1}{Y}$$

So, the material with the smallest slope has the largest Young's modulus.

From the figure, line A is the flattest relative to the stress axis among the labeled materials according to the solution explanation, so it has the largest Young's modulus.

Therefore, the correct option is A.

Given: The graph is strain on Y-axis and stress on X-axis.

Find: The material with maximum Young's modulus.

A common confusion is to treat this as a stress-strain graph. But here the axes are reversed.

For Young's modulus,

$$Y = \frac{\sigma}{\epsilon}$$

Hence on this graph,

$$\frac{\epsilon}{\sigma} = \frac{1}{Y}$$

This means:

• larger slope $\Rightarrow$ smaller $Y$
• smaller slope $\Rightarrow$ larger $Y$

The solution states that material A has the least steep slope relative to the stress axis, while D is steeper. Therefore A has the highest value of Young's modulus.

Thus, the correct option is A.