Description:
In this article the force in Physics is described with two different behaviors: like vector and covector. The forcebehaves like vector (with direction), in the Second Law of Newton, when this one is proportionate with theacceleration. On the other hand, the force behaves like covector (without direction), if this one is related the scalar ofwork. This is part of the duality concept. So that the space of vectors exists, the convector space must exist. Each formcannot exist by itself.