Miles per hour
Miles per hour is a unit of speed, expressing the number of international miles covered per hour. The common abbreviation in everyday use is mph, although mi/h, using the SI method of expressing derived units, is sometimes used, especially in the United States. The preferred SI unit for velocity is m/s, although km/h is often used as a replacement for mph.
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
Miles per hour is the unit used for speed limits on roads in the US and Britain.
Examples of speeds in mph
| 3 mph | Walking speed |
| 15 mph | Bicycling speed |
| 23 mph | Top speed of a running human. (34 ft/s) |
| 30 mph | Residential speed limit Top speed of a running cat, or dog |
| 50–60 mph | Speed limit on a major road Top speed of an antelope |
| 70 mph | Highway or motorway speed Top speed of a cheetah |
| 180 mph | High-speed train |
| 625 mph | Airliner cruising speed |
| 761 mph | The approximate speed of sound (at sea level) |
| 763 mph | Current world land speed record |
| 16,250 mph | Re-entry speed of the space shuttle |
| 25,200 mph | Earth's escape velocity |
| 670,616,629 mph | Speed of light |