ELASTICITY - the ability to flex and bend when forces are applied and then return to normal when the forces are removed ( eg. an elastic band).

PLASTICITY - the ability of a material to be changed in shape permanently by external blows or pressure, without cracking or breaking (eg. plasticine) Some materials become more plastic when heated.
Two other properties of materials are associated with the term plasticity these are MALLEABILITY and DUCTILITY.

Don't bash it until you know what's going to happen.

Malleability - if a material can be deformed in all directions by such as hammering and pressing without it cracking or

splitting it is said to be malleable. These materials need not be strong but they need to be 'plastic'. That is they need to be able to be bent often without breaking.

Ductility - usually means the ability of a material to be stretched twisted or bent without breaking. All ductile materials are malleable but all malleable materials are not necessarily ductile. For example clay can be easily shaped but when you try to stretch it, it breaks.

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