The tension force is the force that is transmitted through a string, rope, cable or wire when it is pulled tight by forces acting from opposite ends. The tension force is directed along the length of the wire and pulls equally on the objects on the opposite ends of the wire.
In physics, tension describes the pulling force exerted by each end of a string, cable, chain, or similar one-dimensional continuous object, or by each end of a rod, truss member, or similar three dimensional object.
At the atomic level, tension is produced when atoms or molecules are pulled apart from each other and gain electromagnetic potential energy. Each end of a string or rod under tension will pull on the object it is attached to, to restore the string/rod to its relaxed length.
Tension is the opposite of compression.
