A collection of physics terms for quick reference

Magnitude

Quick Definition: The size or quantity of a physical property.

Origin: Latin "magnitudo" meaning "greatness".

The magnitude of a physical quantity is its size or quantity, irrespective of its direction or sign. For example, the magnitude of a vector is the length of the vector, regardless of its direction.

Scalar

Quick Definition: A value with no direction, only magnitude.

Origin: Latin "scalaris" meaning "of or pertaining to a ladder".

A scalar is a physical quantity that has magnitude only and no direction in space. Examples of scalars include mass, temperature, and speed.

Vector

Quick Definition: A quantity with both magnitude and direction.

Origin: Latin "vector" meaning "carrier" or "one who carries".

A vector is a mathematical object that represents a physical quantity with both magnitude and direction. Unlike scalars, vectors require both a numerical value (magnitude) and a specified direction to be fully defined. Examples of vectors include displacement, velocity, force, and acceleration. In physics and engineering, vectors are often represented graphically as arrows, where the length of the arrow indicates the magnitude and the orientation shows the direction.