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Single conversion
To convert from rotation per minute (rpm) to kilohertz (kHz), use the following formula:
Let's convert 5 rotation per minute (rpm) to kilohertz (kHz).
Using the formula:
Therefore, 5 rotation per minute (rpm) is equal to kilohertz (kHz).
Here are some quick reference conversions from rotation per minute (rpm) to kilohertz (kHz):
| rotations per minute | kilohertz |
|---|---|
| 0.000001 rpm | kHz |
| 0.001 rpm | kHz |
| 0.1 rpm | kHz |
| 1 rpm | kHz |
| 2 rpm | kHz |
| 3 rpm | kHz |
| 4 rpm | kHz |
| 5 rpm | kHz |
| 6 rpm | kHz |
| 7 rpm | kHz |
| 8 rpm | kHz |
| 9 rpm | kHz |
| 10 rpm | kHz |
| 20 rpm | kHz |
| 30 rpm | kHz |
| 40 rpm | kHz |
| 50 rpm | kHz |
| 100 rpm | kHz |
| 1000 rpm | kHz |
| 10000 rpm | kHz |
For all Frequency converters, choose units using the From/To dropdowns above.
Simply put, rotations per minute (RPM) measures the speed at which something is spinning.
It counts the number of full turns an object completes in one minute. From car engines to computer hard drives, RPM is a key indicator of performance and speed.
The concept of RPM (rotations per minute) gained popularity during the Industrial Revolution, thanks in large part to Scottish engineer James Watt.
While developing his steam engine, Watt needed a way to compare its power output to that of a horse. To do this, he determined how many times a horse could turn a mill wheel in one minute.
He utilized this rotational measurement to help establish the definition of horsepower. As a result, RPM became a crucial metric for quantifying the performance and work capacity of mechanical engines—a practice that continues to this day.
You encounter RPM every day in common technology.
In your car, the tachometer displays the engine's speed in rotations per minute, indicating how fast the crankshaft is spinning. A higher RPM generally means more power is being produced.
Computer hard disk drives (HDDs) also use RPM to measure their performance; a 7200 RPM drive can read and write data faster than a 5400 RPM drive.
RPM ratings, which denote motor speed and efficiency, are also found on household appliances such as blenders, washing machines, and fans.
Although RPM is a common unit, physics and engineering often use hertz (Hz) for frequency and radians per second (rad/s) for angular velocity.
The conversion is straightforward:
To Hertz (Hz): Because a minute has 60 seconds, you divide the RPM value by 60.
To Radians per Second (rad/s): One complete rotation is equivalent to 2π radians. To convert RPM to radians per second, multiply the RPM value by 2π, then divide by 60.
A kilohertz (kHz) is a unit of frequency in the International System of Units (SI), equal to one thousand hertz (1000 Hz). The plural form is kilohertz.
It's a term you'll encounter in everything from sound and radio to the history of computing.
Your ability to perceive sound, from the deepest bass to the highest treble, is measured in hertz and kilohertz.
The range of human hearing typically falls between 20 Hz and 20 kilohertz (20,000 Hz).
The frequencies most sensitive to the human ear, particularly for understanding speech, are concentrated in the range of 1 to 4 kHz. This is why audio engineers and audiologists pay close attention to this specific spectrum when mixing music or conducting hearing tests.
Kilohertz is the fundamental unit used for AM (Amplitude Modulation) radio broadcasting.
AM radio stations operate in a frequency range from 535 to 1705 kilohertz in the Americas, often referred to as the medium wave band.
Each station is assigned a specific frequency, like 820 kHz or 1010 kHz, which your radio receiver tunes into to capture the broadcast signal. This contrasts with FM radio, which broadcasts in the much higher megahertz (MHz) range.
While today's computers boast processor speeds in gigahertz (GHz), the pioneers of computing operated at much slower speeds measured in kilohertz.
For instance, the Intel 4004, the world's first commercial microprocessor, was released in 1971 with a clock speed of just 740 kHz.
Beyond computing, kilohertz frequencies are also crucial in other technologies. A key example is medical ultrasound, where transducers emit sound waves in the high kHz to low MHz range to create diagnostic images of the body's organs and tissues.