| Metre per second squared | |
|---|---|
| Unit system | SI |
| Unit of | acceleration |
| Symbol | m/s2 |
Themetre per second squared ormetre per square second is theunit ofacceleration in theInternational System of Units (SI). As aderived unit, it is composed from theSI base units of length, themetre, and of time, thesecond. Its symbol is written in several forms asm/s2,m·s−2 orms−2,, or less commonly, as(m/s)/s.[1]
As acceleration, the unit is interpreted physically as change in velocity or speed per time interval, i.e.metre per second persecond and is treated as a vector quantity.
When an object experiences a constant acceleration of one metre per second squared (1 m/s2) from a state of rest, it achieves the speed of 5 m/s after 5 seconds and 10 m/s after 10 seconds. The average accelerationa can be calculated by dividing the speedv (m/s) by the timet (s), so the average acceleration in the first example would be calculated:
Newton's second law states that force equals mass multiplied by acceleration.The unit of force is thenewton (N), and mass has the SI unitkilogram (kg). One newton equals onekilogram metre per second squared. Therefore, the unit metre per second squared is equivalent to newton per kilogram, N·kg−1, or N/kg.[2]
Thus, the Earth's gravitational field (near ground level) can be quoted as 9.8 metres per second squared, or the equivalent 9.8 N/kg.
Acceleration can be measured in ratios to gravity, such asg-force, andpeak ground acceleration in earthquakes.
The "metre per second squared" symbol is encoded byUnicode at code pointU+33A8 ㎨SQUARE M OVER S SQUARED. This is for compatibility with East Asian encodings and not intended to be used in new documents.[3]
| Base value | (Gal, or cm/s2) | (ft/s2) | (m/s2) | (Standard gravity,g0) |
|---|---|---|---|---|
| 1 Gal, or cm/s2 | 1 | 0.0328084 | 0.01 | 1.01972×10−3 |
| 1 ft/s2 | 30.4800 | 1 | 0.304800 | 0.0310810 |
| 1 m/s2 | 100 | 3.28084 | 1 | 0.101972 |
| 1g0 | 980.665 | 32.1740 | 9.80665 | 1 |