# Rotational speed

Object rotating around an axis is the number of turns of the object divided by time, specified as revolutions per minute (rpm), cycles per second (cps), radians per second (rad/s), etc.

- Rotational speed75 related topics

## Revolutions per minute

Number of turns in one minute.

Number of turns in one minute.

It is a unit of rotational speed or the frequency of rotation around a fixed axis.

## Speed

Object is the magnitude of the rate of change of its position with time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity.

Object is the magnitude of the rate of change of its position with time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity.

Rotational speed (or angular speed) involves the number of revolutions per unit of time.

## Locomotive

Rail transport vehicle that provides the motive power for a train.

Rail transport vehicle that provides the motive power for a train.

However, a turbine's power output and efficiency both drop dramatically with rotational speed, unlike a piston engine, which has a comparatively flat power curve.

## Rifle

Long-barreled firearm designed for accurate shooting, with a barrel that has a helical pattern of grooves cut into the bore wall.

Long-barreled firearm designed for accurate shooting, with a barrel that has a helical pattern of grooves cut into the bore wall.

Bullets leaving a rifled barrel can spin at a rotational speed of over 100,000 revolutions per minute (rpm) (or over about 1.67 kilohertz, since 1 RPM = 1/60 Hz).

## Shot put

Track and field event involving "putting" a heavy spherical ball—the shot—as far as possible.

Track and field event involving "putting" a heavy spherical ball—the shot—as far as possible.

Another purpose of the spin is to build up a high rotational speed, by swinging the right leg initially, then to bring all the limbs in tightly, similar to a figure skater bringing in their arms while spinning to increase their speed.

## Torque

Newton-metre .

Newton-metre .

For example, if rotational speed (revolutions per time) is used in place of angular speed (radians per time), we multiply by a factor of 2 radians per revolution.

## Wankel engine

Type of internal combustion engine using an eccentric rotary design to convert pressure into rotating motion.

Type of internal combustion engine using an eccentric rotary design to convert pressure into rotating motion.

Since Wankel engines operate at a relatively high rotational speed, at 6,000rpm of output shaft, the Rotor makes only 2,000 turns.

## Mariner 1

The first spacecraft of NASA's interplanetary Mariner program.

The first spacecraft of NASA's interplanetary Mariner program.

The planet's rotation rate was uncertain, though JPL scientists had concluded through radar observation that Venus rotated very slowly compared to the Earth, advancing the long-standing (but later disproven ) hypothesis that the planet was tidally locked with respect to the Sun (as the Moon is with respect to the Earth).

## Rotation

Circular movement of an object around an axis of rotation.

Circular movement of an object around an axis of rotation.

The speed of rotation is given by the angular frequency (rad/s) or frequency (turns per time), or period (seconds, days, etc.).

## Saab 2000

Twin-engined high-speed turboprop airliner built by Swedish aircraft manufacturer Saab.

Twin-engined high-speed turboprop airliner built by Swedish aircraft manufacturer Saab.

The Dowty-Rotol propellers are 12.5 ft in diameter, and they have a slow rotational speed of 1,100 rpm at takeoff and 950 rpm in cruise.