# metre per second squared

##### SI coherent derived unit
Name Symbol Derived quantity
metre per
second squared
m s−2 acceleration ### Definition

The metre per second squared, symbol m s−2, is the SI coherent derived unit of acceleration.

An object with a constant acceleration of one metre per second squared experiences an increase in velocity of one metre per second over a period of one second.

Acceleration is a vector quantity, it has magnitude and direction.

### Physics

Acceleration is the rate of change of velocity of an object with respect to time. An object’s acceleration is the net result of all forces acting on the object. Newton’s Second Law states that force is proportional to mass multiplied by acceleration. $F = ma$

The unit of force is the newton, symbol N, and mass has the SI unit kilogram, symbol kg.

One newton equals one kilogram metre per second squared. Therefore, the unit metre per second squared is equivalent to newton per kilogram, N kg−1, or N/kg.

The Earth’s gravitational field at sea level is approximately 9.8 m s−2, or 9.8 N/kg.