Foot per second (ft/s) - Unit Information & Conversion

Symbol:ft/s
Plural:feet per second
Category:Speed

What is a Foot per second?

Definition

Feet per second (ft/s, fps, or ft/sec) is a unit of speed in the imperial and US customary systems. It measures the distance in feet traveled in one second.

History

The foot as a unit of length has ancient origins, and the second became standardized more recently. Feet per second emerged as a logical unit for measuring speed in contexts where feet were the standard measure of distance, particularly before widespread metrication.

Common Uses

  • Physics & Engineering (Imperial/US): Used in calculations involving velocity and acceleration in systems using imperial units, particularly in older texts or specific industries (e.g., some aerospace applications).
  • Ballistics: Often used to measure the muzzle velocity of firearms.
  • Fluid Dynamics (Imperial/US): Can be used to express the speed of fluid flow in pipes or channels in US customary units.
  • Some Scientific Instruments: Certain instruments might output readings in ft/s depending on their design and intended application region.

Unit FAQs

Is ft/s commonly used for everyday speed?

No, miles per hour (mph) is much more common for everyday speeds (like driving) in countries using the imperial/US customary system. ft/s is more technical.

Is ft/s an SI unit?

No, it belongs to the imperial and US customary systems. The SI unit for speed is meters per second (m/s).

How do you convert ft/s to mph?

Divide the speed in ft/s by 1.46667. So, 88 ft/s is approximately 60 mph.

How do you convert ft/s to m/s?

Multiply the speed in ft/s by 0.3048. So, 10 ft/s is equal to 3.048 m/s.

Foot per second Conversion Formulas

To Meter per second:

1 ft/s = 0.3048 m/s
Example: 5 feet per second = 1.524 meters per second

To Kilometer per hour:

1 ft/s = 1.09728 km/h
Example: 5 feet per second = 5.4864 kilometers per hour

To Mile per hour:

1 ft/s = 0.681818 mph
Example: 5 feet per second = 3.409091 miles per hour

To Knot:

1 ft/s = 0.592484 kn
Example: 5 feet per second = 2.962419 knots

To Mach number:

1 ft/s = 0.000889 Mach
Example: 5 feet per second = 0.004443 Mach numbers

To Speed of light:

1 ft/s = 1.0167e-9 c
Example: 5 feet per second = 5.0835e-9 speed of light

Convert Foot per second

Need to convert Foot per second to other speed units? Use our conversion tool.