mph

1 the ratio of the distance traveled (in miles) to the time spent traveling (in hours) [syn: miles per hour]

2 a speedometer reading for the momentary rate of travel [syn: miles per hour]

The mile per hour is a unit of speed, expressing the number of international miles covered per hour.

It is currently the unit used for speed limits, and speeds, on roads in the United Kingdom, United States and other nations. It is also used to express the speed of delivery of a ball in various sporting events, such as cricket, tennis, and baseball at the higher levels of competition. A common abbreviation is mph or MPH, although mi/h is sometimes used in technical publications.

In the International System of Units (SI), the unit of speed or velocity is m/s. Road traffic speeds, in most countries, are quoted in km/h. Nautical and aeronautical applications, however, favor the knot as a common unit of speed: one knot is one nautical mile per hour.

Conversions

1 mph is equal to:

• 0.44704 m/s, the SI derived unit
• 1.609344 km/h
• 22/15 =1.4667 feet per second
• approx. 0.868976 knots

When converting miles per hour to another unit of measurement, or vice versa, it helps to know exactly how miles and hours are related to other units of distance and time, respectively. For example, 1 mile is equal to 5,280 feet, 1,760 yards, or 1,609.344 meters. Likewise, 1 hour is equal to 60 minutes, or 3,600 seconds.

See also

• Acceleration
• Light-year
• Orders of magnitude (speed)
• Velocity