Revolutions per Minute to Revolutions per Hour Converter

Revolutions per minute (rpm) is a unit of rotational frequency representing the number of complete rotations around a fixed axis in one minute. It's one of the most common units for measuring rotational speed in mechanical systems.

RPM became standard with the development of mechanical machinery during the Industrial Revolution. It provided an intuitive way to measure and specify rotational speeds for engines, motors, and machinery, becoming universally adopted in mechanical engineering.

RPM is extensively used in automotive engines, electric motors, machinery, and mechanical systems. It's standard for engine specifications, motor ratings, turntable speeds, and virtually all rotating mechanical equipment specifications.

Revolutions per hour (rph) is a unit of rotational frequency representing the number of complete rotations around a fixed axis in one hour. It's used for very slow rotational systems and astronomical observations.

RPH became useful for describing very slow rotational systems such as astronomical observations, large industrial equipment, and systems where rotational speeds are extremely low. It provided appropriate scaling for applications where RPM would result in very small decimal numbers.

RPH is used for astronomical observations (planetary rotation), very slow industrial processes, large rotating equipment, and systems with extremely low rotational speeds. It's found in astronomical calculations and specifications for very slow rotating machinery.