# 1.5 (e) Scalars and vectors

A **vector** has a specific direction as well as a size, with a unit: pressure, electrical current and even the flow of heat are all vectors. A **vector** quantity has both **magnitude** and **direction**.

Force, velocity, weight, and acceleration are examples of vector quantities.

A **scalar** quantity has size only, with a unit. There are many more scalar quantities: temperature, work, power and electrical resistance are all scalars. A **scalar** quantity has only **magnitude**.

Speed, density, energy, and mass are examples of a scalar quantity.