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by 00098345 3612 days ago
> Elasticity is how much you can deform (stretch) an object, before the deformation is no longer reversible. Think of a rubber band, you can stretch it a little, and it returns to its original shape. Stretch it a lot, and it breaks down and does not return to its original shape. > Plasticity is how much you can deform an object before it breaks. This is the snapping point in the rubber band, where it completely breaks.

These both are completely false.

Elasticity is the idealistic property of a solid material to get back to it's original shape after a deformation force is retracted. (property of most solid metals where stress is much below the yield point)

Plasticity is the idealistic property of a solid material to stay in the deformed shape after a deformation force is retracted. (Plasticine)

1 comments

You are correct, but the statement you're quoting can be easily corrected: replace "elasticity" with "The elastic limit of a material". The elastic limit is also conventionally called the "yield strength".

"Plastic limit" is not a real term, but if it were, it might be a synonym for "ultimate tensile strength". There's also compressive strength and shear strength.