Definition:Magnitude

Definition
The magnitude (or size) of a quantity (either vector or scalar) is a measure of how big it is.

It is usually encountered explicitly in the context of vectors:

If $\mathbf v$ is the vector quantity in question, then its magnitude is denoted:
 * $\size {\mathbf v}$

or
 * $v$

Also defined as
In Euclidean number theory, the term magnitude is used to mean positive real number.

Also known as
The magnitude of a vector is also referred to as its module or modulus in some older books.

Some sources refer to it as the absolute value of the vector.

Also see

 * Definition:Direction


 * Definition:Vector Length
 * Definition:Absolute Value