AS Physics - Mechanics.

Usually two equal and opposite forces acting on both ends of a wire in order to stretch it.

Two or more forces that have the effect of reducing the volume of the object on which they are acting, or reducing the length of a spring.

The object will return to its original shape when the deforming force is removed.

The object will not return to its original shape when the deforming force is removed, it becomes permanently deformed.

The point at which elastic deformation becomes plastic deformation.

The energy stored within a stretched or  compressed object (for example a spring).

J

E = work done = 0.5Fx =

The change in length of an object when subjected to tension.

m

The extension of an elastic body is proportional to the force that causes it.

The force per unit cross-sectional area.

Pa

The ration between stress and strain.

Pa

Materials that have a large plastic region, therefore can be drawn into wire; for example, copper.

The maximum stress that can be applied to an object before it breaks.

The maximum tensile force that can be applied to an object before it breaks.

A material that distorts very little even when subject to a large stress and does not exhibit any plastic deformation; for example concrete.

Extension per unit length.

(L change = extension).

A material made of many smaller molecules bonded together, often making tangled long chains. These materials often exhibit very large strains (e.g. 300%), for example rubber.