Metre per second squared

Metre per second squared (symbol: m/s², also written m·s⁻²) is the SI unit for measuring acceleration, which is the rate at which the velocity of an object changes over time. It is derived from the basic units of the metre (distance) and the second (time).

An object with an acceleration of 1 m/s² increases its velocity by 1 metre per second with each passing second. If an object starts from rest and then accelerates at 1 m/s², its velocity will be 1 m/s after one second and 2 m/s after two seconds.

Mathematical definition

Acceleration is the measure of how velocity changes divided by the time interval: a = Δv/Δt. Therefore the unit is (m/s)/s = m/s². In terms of SI base units, it consists of the metre and the second only; mass does not appear in the unit.

Relation to force

Newton's second law relates acceleration to force: F = m·a. Accordingly, one newton (N) is defined as the force that causes an object with a mass of 1 kilogram to accelerate at 1 m/s². Therefore, 1 N = 1 kg·m/s².

Gravitational acceleration on Earth

The acceleration due to gravity at Earth's surface is commonly taken as 9.8 m/s², with the standard value defined as 9.806 65 m/s². This value varies depending on latitude and location.