Kilometres per hour

Kilometers per hour, kilometers per hour colloquially, rare kilometers per hour, kilometers per hour or kilometers per hour ( unit symbol: km / h) is a unit of speed. It is used mainly in transport, for example, used for the speed in traffic or for travel speed, since there Distances are usually measured in kilometers and time in hours - instead of in meters and seconds, which is the SI unit of speed m / s is based. The two associated metrics have the same order of magnitude.

Definition

An object for an hour moves by 1 km / h covers a distance of one kilometer.

Colloquial language

Colloquially often the spoken form "ka -em- ha" used, instead of " km / h" also leads to the way of writing " kmh ". Just as kilometers per hour is the (physical ) technical terminology wrong, as this juxtaposition mile times would be there for the product hour. But the German Language Society points out that the word formation of composites, the relationship of the verbal elements not subject to any rules and the concept is quite right and proper. At speeds of motor vehicles is often entirely omitted a name ( "He's been flashed in the construction site at 120. " ), As well as in the preparation of velocities on the appropriate traffic signs. Long road signs were in use for example in the old federal states of Germany, where only the wrong unit was "km" contain ( without the " / h").

Conversion between km / h and m / s

The unit km / h is often preferred SI unit m / s (meters per second). So you can convert the two associated metrics into one another:

So:

Alternatives

In some countries, such as in the U.S. or the UK, where the metric system is not mandatory, often speeds in miles per hour (mph ) can be specified ( 1 mph = 1.609 km / h ). In the nautical and aviation are speed values ​​in knots ( kn), ie nautical miles per hour, customary (1 kn = 1.852 km / h ).