Stress-strain and Force-extension graphs

Yield point

Where the material starts to stretch without any extra load

Order of stress-strain points

-Limit of proportionality

-Elastic limit

-Yield point

Stiff

Difficult to stretch or compress

Strong

Have a large breaking stress

What does it mean if a line stops on a stress-strain graph

The material has broken

Difference between what affects a force-extension graph from a stress-strain graph

Dimensions of the material affect force-extension

Unloading line

The line on a force-extension graph as the force is removed

Explain the unloading line of a force-extension graph

Parallel to the loading line as it has the same k and the forces between the atoms are the same

Explain when the unloading line would not meet the origin of the force-extension graph

If the material has been stretched beyond the elastic limit, it has now been permanently stretched