The stress versus strain graph for two materials A and B are shown in fig. the graph are on the same scale. ltbr. (a) Which material has greater Young's modulus?
(b) which of the two is stronger material?

Explanation

Answer: (a) A (b) A
(a) For a given strain, the stress for material A is more than it is for material B, as shown in the two graphs.
Young's modulus `=("Stress")/("Strain")`
For a given strain, if the stress for a material is more, then Young’s modulus is also greater for that material. Therefore, Young’s modulus for material A is greater than it is for material B.
(b) The amount of stress required for fracturing a material, corresponding to its fracture point, gives the strength of that material. Fracture point is the extreme point in a stress-strain curve. It can be observed that material A can withstand more strain than material B. Hence, material A is stronger than material B.