The dimensional formula of velocity is [LT⁻¹], where L represents length and T represents time.
This means that velocity is expressed in terms of units of length per unit time. Common units of velocity include meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), and so on.
To understand the dimensional formula, consider the definition of velocity: the rate of change of displacement with respect to time. Displacement is a measure of length, and time is a fundamental dimension. Therefore, velocity is measured as the ratio of a length unit to a time unit, giving it the dimension of [LT⁻¹].