Revolutions per Second (rps) - Unit Information & Conversion

Symbol:rps
Plural:rps
Category:Frequency

🔄 Quick Convert Revolutions per Second

What is a Revolutions per Second?

RPS (revolutions per second) measures rotational speed as the number of complete rotations in one second. Equal to hertz (Hz) for rotational motion. Used for high-speed machinery, turbines, and physics calculations.

History of the Revolutions per Second

Direct measurement of rotational frequency. Mathematically equivalent to hertz, but RPS emphasizes rotational context while Hz is general frequency. Used in engineering and physics for high-speed rotating systems.

Quick Answer

What is RPS? RPS (revolutions per second) measures rotational speed as complete rotations in one second. 1 RPS = 1 Hz = 60 RPM. Used for high-speed turbines, centrifuges, and machinery where per-second measurement is more convenient than RPM. 1 RPS = 1 Hz = 60 RPM. Use our frequency converter for instant conversions.

Key Facts: Revolutions per Second

Property Value
Symbol rps
Quantity Frequency
System Metric/SI Derived
Derived from Hertz
Category Frequency
Standard Body NIST / ISO

Definition

1 RPS = 1 revolution per second = 1 Hz = 60 RPM = 360°/second = 2π radians/second

RPS vs RPM vs Hz

Understanding the relationship between rotational measurements:

  • RPM = cycles per MINUTE (most common for machinery)
  • RPS = cycles per SECOND (more convenient for high speeds)
  • Hz = cycles per SECOND (generic frequency term)
  • Conversion: 1 RPS = 60 RPM = 1 Hz (numerically identical to Hz)
  • Why three units? Different fields and speed ranges use different conventions

Common Uses

High-Speed Turbines: Gas turbines, steam turbines, hydroelectric turbines (hundreds to thousands of RPS). Centrifuges: Ultra-high-speed laboratory and industrial centrifuges for separation. Physics: Rotational dynamics, angular velocity, kinetic energy calculations. Machinery: High-speed motors, spindles, grinders, pumps.

Real-World Examples

Industrial High-Speed Machinery

Systems where RPS notation is more common than RPM:

Equipment Typical Speed RPS RPM Frequency (Hz) Power/Purpose
Gas turbine (small) 15,000-30,000 250-500 15,000-30,000 250-500 Hz Electricity generation
Gas turbine (large) 3,000-6,000 50-100 3,000-6,000 50-100 Hz Power plant
Jet engine 10,000-30,000 167-500 10,000-30,000 167-500 Hz Aircraft thrust
Steam turbine 1,500-5,000 25-83 1,500-5,000 25-83 Hz Power generation
Hydroelectric turbine 250-1,000 4-17 250-1,000 4-17 Hz Water power
Compressor turbine 5,000-50,000 83-833 5,000-50,000 83-833 Hz Air compression

Note: High-speed turbines use RPS to avoid unwieldy 5-digit RPM numbers

Ultra-High-Speed Centrifuges

Laboratory and industrial separation equipment:

Centrifuge Type Speed RPS RPM G-Force Application
Tabletop centrifuge 1,000-3,000 17-50 1,000-3,000 10-500 g General lab
Microcentrifuge 5,000-10,000 83-167 5,000-10,000 500-5,000 g DNA/cells
Ultracentrifuge 50,000-100,000 833-1,667 50,000-100,000 100,000-500,000 g Protein study
Analytical ultracentrifuge 100,000-150,000 1,667-2,500 100,000-150,000 500,000-1,000,000 g Molecular analysis

Relationship: G-force = (RPS)² × radius(cm) × 0.0399

Precision Machine Tools

Spindle speeds in manufacturing:

Tool Type Typical Speed RPS RPM Purpose
Manual lathe 500-3,000 8-50 500-3,000 Metal turning
CNC mill (general) 1,000-10,000 17-167 1,000-10,000 Precision milling
CNC mill (high-speed) 10,000-50,000 167-833 10,000-50,000 Aluminum, plastics
Dental drill 20,000-40,000 333-667 20,000-40,000 Tooth work
Industrial grinder 5,000-15,000 83-250 5,000-15,000 Material removal
Polishing wheel 3,000-5,000 50-83 3,000-5,000 Surface finishing

Speed advantage: Higher RPS = faster material removal, better finish

Speed Comparison: RPS vs RPM

When to use each unit:

Application Typical Speed Better As Why
Car engine 1,000-7,000 RPM 17-117 RPS RPM is standard (smaller numbers)
Hard drive 5,400-7,200 RPM 90-120 RPS Either works (RPM is conventional)
Turbine 10,000-50,000 RPM 167-833 RPS RPS avoids 5-digit numbers
Jet engine 20,000-50,000 RPM 333-833 RPS RPS is clearer for this range
Tiny motor 100 RPM 1.67 RPS RPM is better (whole numbers)
Laboratory centrifuge 100,000 RPM 1,667 RPS RPS is more manageable

Rule of thumb: Use RPS when base number would exceed 10,000 RPM

Converting Between Units

Quick reference table:

Speed RPS RPM Hz
Very slow 0.5 30 0.5
Slow 10 600 10
Medium 50 3,000 50
Fast 100 6,000 100
Very fast 500 30,000 500
Extremely fast 1,000 60,000 1,000
Ultra-high 2,000 120,000 2,000

Revolutions per Second Conversion Formulas

To Hertz:

1 rps = 1 Hz
Example: 5 rps = 5 hertz

To Millihertz:

1 rps = 1000 mHz
Example: 5 rps = 5000 millihertz

To Kilohertz:

1 rps = 0.001 kHz
Example: 5 rps = 0.005 kilohertz

To Megahertz:

1 rps = 0.000001 MHz
Example: 5 rps = 0.000005 megahertz

To Gigahertz:

1 rps = 1.0000e-9 GHz
Example: 5 rps = 5.0000e-9 gigahertz

To Terahertz:

1 rps = 1.0000e-12 THz
Example: 5 rps = 5.0000e-12 terahertz

To Revolutions per Minute:

1 rps = 60 rpm
Example: 5 rps = 300 rpm

To Beats per Minute:

1 rps = 60 bpm
Example: 5 rps = 300 bpm

To Cycles per Second:

1 rps = 1 cps
Example: 5 rps = 5 cps

To Radians per Second:

1 rps = 6.283185 rad/s
Example: 5 rps = 31.415927 rad/s

Frequently Asked Questions

Formula: RPM = RPS × 60 Examples:

Convert Revolutions per Second

Need to convert Revolutions per Second to other frequency units? Use our conversion tool.