Why is ball speed at Wimbledon given in miles per hour when the United Kingdom has long since metricated?
Keep in mind that the imperial system originated in the UK, and most sports are old enough that all the parameters were formed back when the imperial system was still used in full. Look at soccer/football in the UK. They still use the terms "6-yard-box" and "18-yard-box", and they still require defenders to be "10 yards" away when taking a free kick. All sports were founded under imperial measurements, so those terms are usually still used.
Hey man, In American usage, In 1793, Thomas Jefferson requested artifacts from France that could be used to adopt the metric system in the United States In 1832, the customary system of units was formalized. United States Congress protected the use of the metric system in commerce with the Metric Act of 1866 Under the Mendenhall Order in 1893, metric standards, were adopted The ONLY use the Americans have is the Two Litre Soda Bottle. Metric bolts on Export Vehicles. So, why not England their Motherland retain the Imperial Measurements.
BECAUSE DUMB *** AMERICANS CAN NOT CONVERT MPH KPH
We still use mph for speeds. We are partially metricated.
The UK only went metric because the French insisted on it as a condition of being allowed to join the EEC / EU, but now with the Brexit the UK is going back to Imperial Units.