- Alternate uses: rpm (disambiguation)
for 'revolutions per minute', rpm
is a unit
for rotational speed. Gramophone
or analogue disc records
typically rotate with 33, 45, or 78 rpm. Aircraft piston motors can rotate with 8000 rpm. An automobile
typically makes between 700 and 7000 rpm; a racing engine's limits are much higher, as high as 19,000 rpm in Formula 1
. Gas turbine
engines rotate at tens of thousands of rpm.
Standards bodies generally recommend the symbol 'r/min', which better follows the general principles for forming unit symbols.
The SI unit of rotational speed is the radian per second: 1 r/min = 0.104 719 76 rad/s.