# Definition:Vector Quantity/Arrow Representation

## Definition

A vector quantity $\mathbf v$ is often represented diagramatically in the form of an arrow such that:

its length is proportional to the magnitude of $\mathbf v$
its direction corresponds to the direction of $\mathbf v$.

The head of the arrow then indicates the positive sense of the direction of $\mathbf v$.

It can be rendered on the page like so:

It is important to note that a vector quantity, when represented in this form, is not in general fixed in space.

All that is being indicated using such a notation is its magnitude and direction, and not, in general, a point at which it acts.