Miles per hour examining speeds in both kilometres per hour and miles per hour. The judge was quoted as saying the speed seemed "very excessive" at 180 km/h but did not look "as bad" at 112 mph; a reduced fine was still imposed on the speeding driver. Miles per hour is the unit also used in the Canadian rail system, which uses km/h on roads. Nautical and aeronautical applications favour the knot as a common unit of speed. (One knot is one nautical mile per hour, with a nautical mile being exactly 1,852 meters or about 6,076 feet.) In some countries mph may
Nautical mile of latitude is not constant, but about at the poles and at the Equator, with a mean value of . Other countries measure the minute of arc at 45 degrees latitude, giving the nautical mile a length of . In 1929, the international nautical mile was defined by the First International Extraordinary Hydrographic Conference in Monaco as precisely 1,852 metres. Imperial units and United States customary units used a definition of the nautical mile based on the Clarke (1866) Spheroid. The United States nautical mile was defined as based in the Mendenhall Order foot of 1893. It was abandoned in