Kilometre per hour
From open-encyclopedia.com - the free encyclopedia.
Kilometre per hour (American spelling: kilometer per hour) is a unit of both speed (scalar) and velocity (vector). The abbreviation is km/h or km·h-1, although the unit is sometimes written colloquially as kph, kmph, or km/hr.
By definition, an object travelling at a speed of 1 km/h for an hour would move 1 kilometre.
- 1 km/h = 0.278 m·s-1, the SI derived unit of speed metre per second (definitely an approximation)
- 1 km/h = 0.621 mi/h = 0.911 ft/s (may be an approximation)
- 1 m/s = 3.6 km/h (exact)
Examples of speeds in km/h
| 5 km/h | Walking speed |
| 20 km/h | Easy bicycling speed |
| 50 km/h | Residential speed limit Top speed of a running cat, dog or human |
| 80-90 km/h | Speed limit on a major road Top speed of an antelope |
| 110-120 km/h | Highway or motorway speed Top speed of a cheetah |
| 300 km/h | High-speed train |
| 1000 km/h | Airliner cruising speed |
| 1200 km/h | The approximate speed of sound (at sea level) |
| 1228 km/h | Current world land speed record |
| 26,000 km/h | Re-entry speed of the space shuttle |
| 40,320 km/h | Earth's escape velocity |
| 1,079,252.849 km/h | Speed of light (exact) |
External link
de:Km/h es:Kilómetro por hora ja:時速
