Materials 2 - Stress, Strain & Youngs Modulus

Up to which point on the stress strain curve shows where the material is undergoing elastic deformation?

• Point A

• Point B

• Point C

• Point D

Answer explanation

The straight line region of the curve is where the material is undergoing elastic deformation

The graph shows tensile tests on four material samples. Which material has the highest modulus of elasticity?

• Material A

• Material B

• Material C

• Material D

Answer explanation

Material A has the steepest gradient, therefore, the highest modulus of elasticity

The graph shows tensile tests on three material samples. Which material has brittle characteristics?

• Material A

• Material B

• Material C

• You can't tell from this graph

Answer explanation

Material A shows very little plastic deformation

A 3.0 m length of copper wire of diameter 0.4 mm is suspended from the ceiling. When a 0.5 kg mass is suspended from the bottom of the wire it extends by 0.9 mm. What is the tensile stress in the wire?

For the wire in Q4, calculate the strain

For the wire in Q4, calculate Young's Modulus. (Use your answers from Q4 and Q5)