Miles per hour be used to express the speed of delivery of a ball in sporting events such as cricket, tennis and baseball. Miles per hour Miles per hour (abbreviated mph, MPH or mi/h) is an imperial and United States customary unit of speed expressing the number of statute miles covered in one hour. It is used in the United States, United Kingdom and many Commonwealth nations, particularly in the Caribbean region. Speed limits and road traffic speeds are given in miles per hour in the following jurisdictions (elsewhere kilometers per hour are used): Road traffic speeds in other countries are indicated in
Holloman High Speed Test Track third rail, approximately 15,000 ft (4,572 m), was added for high-speed, narrow-gauge sleds. In 2000, pulldown extensions of 149 ft (46.4 m) were added to the north end of each rail, bringing the two primary rails to 50,917 feet (15,536 m). The last major upgrade to the primary rail system occurred in 2002, when the narrow-gauge track was lengthened to 20,379 ft (6,212 m). The HHSTT currently holds the world land speed record for rocket sleds set in April 2003, at Mach 8.6, or 9,465 feet per second (2,885 meters per second), or 6,453.409 miles per hour (10,385.755 kilometres per