Question

The stress strain graph of two bodies A and B are given in the figure

1. Which of the material has greater youngs modulus?

2. Which of the two material is preferable to be used as a rope in a crane?

3. Redraw the graph and mark the regions in the graphs where the elastic force is strictly conservative

Answer 1

1. Youngs modulus, Y =  Stress  Strain 
The slope of above graph gives youngs modulus. The body A has larger slope. Hence youngs modulus of ‘A ‘is greater than ‘B’.

2. The fracture point is greater for A. Hence A is stronger. Due to high strength, the material A is used as rope in a crane.

3.

 

Up to the point C, the elastic force is strictly conservative.