2.1 Scalars

2.1 Scalars

Scalars are physical quantities that are described solely by a magnitude (size or amount) without any mention of direction. Thus, scalars are directionless and can be fully characterized by a single number and its associated unit.

Examples:

Mass: The amount of matter in an object. For example, $2\,\mathrm{kg}$.

Distance: The total length of the path travelled by an object. Respective of the direction. For example, $50\,\mathrm{m}$.

Speed: The rate at which an object covers distance. For example, $40\,\mathrm{km\,h^{-1}}$.

Time: The duration between two events taking place. For example, $20\,\mathrm{s}$.

Energy: The capacity to do work. For example, $25\,\mathrm{J}$.

Temperature: A measure of the average kinetic energy of particles in a substance. For example, $20^{\circ}\mathrm{C}$.