Metre per second

"M/s" redirects here. For the BDSM arrangement, see Master/slave (BDSM). For the maritime prefix designation, see Motor ship.

"mps" redirects here. For the three-letter acronym, see MPS (disambiguation).

Metre per second (U.S. spelling: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in seconds.

The official SI symbolic abbreviation is m·s⁻¹, or equivalently either m/s or $\tfrac{\mbox{m}}{\mbox{s}}$.^[1] Where metres per second are several orders of magnitude too slow to be convenient, such as in astronomical measurements, velocities may be given in kilometres per second, where 1 km/s is 1000 metres per second.

Conversions

1 m/s is equivalent to:

= 3.6 km·h⁻¹ (exactly)

≈ 3.2808 feet per second (approximately)

≈ 2.2369 miles per hour (approximately)

≈ 1.9438 knots (approximately)

1 foot per second = 0.3048 m·s⁻¹ (exactly)

1 mile per hour = 0.44704 m·s⁻¹ (exactly)

1 km·h^-1 ≈ 0.2778 m·s⁻¹ (approximately)

1 kilometre per second is equivalent to:

≈ 0.6213 miles per second (approximately)

≈ 2237 miles per hour (approximate)

Relation to other measures

Although m·s⁻¹ is an SI derived unit, it could be viewed as more fundamental than the metre, since the latter is derived from the speed of light in a vacuum, which is defined as exactly 299 792 458 m·s⁻¹ by the BIPM.^[2] It follows that one metre is the length of the path travelled by light in a vacuum during a time interval of 1/299 792 458 of one second.

See also

• Benz (unit)
• Kilometre per hour
• Orders of magnitude (speed)
• Metre
• Second

References

1. ^ SI brochure, Section 5.1
2. ^ BIPM - metre

External links

• Official BIPM definition of the metre
• Official BIPM definition of the second