Scalar

In mathematics, the meaning of the word scalar depends on the context; it can refer to real numbers or complex numbers or rational numbers, or to members of some other specified field. Generally, when a vector space over the field F is studied, then F is called the "field of scalars".

In physics a scalar is a quantity that can be described by a single number (either dimensionless, or in terms of some physical quantity). Scalar quantities have magnitude, but not a direction and should thus be distinguished from vectors.

Examples of scalar quantities include:

• electric charge
• distance
• energy
• mass
• power
• speed
• temperature
• time
• volume
• work

The term comes the fact that multiplying a vector with a field element results in scaling that vector.