scalar

scalar, a physical quantity that is completely described by its magnitude. Examples of scalars are volume, density, speed, energy, mass, temperature, and time. Other quantities, such as force and velocity, have both magnitude and direction and are called vectors.

Scalars are written using real numbers, which can be positive, negative, or zero. For example, the work done on an object can be a negative number if the object moves in the opposite direction of the applied force. This happens when frictional force slows down a moving body. Scalars can be added, subtracted, multiplied, and divided using the usual rules of algebra.

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Anoushka Pant.