Speed has the dimension length per time. The SI composite unit of speed is the meter per second.

Maple knows the units of speed listed in the following table.

An asterisk ( * ) indicates the default context, an at sign (@) indicates an abbreviation, and under the prefixes column, SI indicates that the unit takes all SI prefixes, IEC indicates that the unit takes IEC prefixes, and SI+ and SI- indicate that the unit takes only positive and negative SI prefixes, respectively.  Refer to a unit in the Units package by indexing the name or symbol with the context, for example, mach[standard] or mph[standard]; or, if the context is indicated as the default, by using only the unit name or symbol, for example, mach or mph.

The units of speed are defined as follows.

A kyne is defined as a centimeter per second.

A mach is defined as the speed of sound at standard temperature and pressure, approximately $331.46$ meters per second.

A mile per hour is defined as a standard mile per hour.

$\mathrm{convert}\left('\mathrm{kyne}'\,'\mathrm{dimensions}'\,'\mathrm{base}'=\mathrm{true}\right)$

$\frac{\mathrm{length}}{\mathrm{time}}$

$\mathrm{convert}\left(2.1\,'\mathrm{units}'\,\frac{'m'}{'s'}\,'\mathrm{mach}'\right)$

$0.006335606107$

$\mathrm{convert}\left(65.0\,'\mathrm{units}'\,'\mathrm{kyne}'\,\frac{'\mathrm{mi}'}{'h'}\right)$

$1.454008590$