Browse Definitions:
Definition

foot per second squared

The foot per second squared (symbolized ft/s 2 or ft/sec 2 ) is the unit of acceleration vector magnitude in the foot-pound-second ( fps ) or English system. This quantity can be defined in either of two senses: average or instantaneous.

For an object traveling in a straight line, the average acceleration magnitude is obtained by evaluating the object's instantaneous linear speed (in feet per second) at two different points t 1 and t 2 in time, and then dividing the distance by the span of time t 2 - t 1 (in seconds). Suppose the instantaneous speed at time t 1 is equal to s 1 , and the instantaneous speed at time t 2 is equal to s 2 . Then the average acceleration magnitude a avg (in feet per second squared) during the time interval [ t 1 , t 2 ] is given by:

a avg = ( s 2 - s 1 ) / ( t 2 - t 1 )

Instantaneous acceleration magnitude is more difficult to intuit, because it involves an expression of motion over an arbitrarily small interval of time. Let p represent a specific point in time. Suppose an object is in motion at about that time. The average acceleration magnitude can be determined over increasingly short time intervals centered at p , for example:

[ p -4, p +4]
[ p -3, p +3]
[ p -2, p +2]
[ p -1, p +1]
[ p -0.5, p +0.5]
[ p -0.25, p +0.25]
.
.
.
[ p - x , p + x ]
.
.
.

where the added and subtracted numbers represent seconds. The instantaneous acceleration magnitude, a inst , is the limit of the average acceleration magnitude as x approaches zero. This is a theoretical value, because it can be obtained only by inference from instantanous speed values determined at the starting and ending points of progressively shorter time spans.

Acceleration, in its fullest sense, is a vector quantity, possessing direction as well as magnitude. For an object moving in a straight line and whose linear speed changes, the acceleration vector points in the same direction as the object's direction of motion. But acceleration can be the result of a change in the direction of a moving object, even if the instantaneous speed remains constant. The classic example is given by an object in circular motion, such as a revolving weight attached to the rim of a wheel. If the rotational speed of the wheel is constant, the weight's acceleration vector points directly inward toward the center of the wheel.

The foot per second squared is not generally used by scientists; the meter per second squared (m/s 2 or m/sec 2 ) is preferred. However, lay people in the United States and, to a lesser extent, in England occasionally define acceleration in terms of feet per second squared.

Also see acceleration , velocity , International System of Units ( SI ), and Table of Physical Units and Constants.

This was last updated in September 2005

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

-ADS BY GOOGLE

Extensions de fichiers et formats de fichiers

Motorisé par:

SearchCompliance

  • cyborg anthropologist

    A cyborg anthropologist is an individual who studies the interaction between humans and technology, observing how technology can ...

  • RegTech

    RegTech, or regulatory technology, is a term used to describe technology that is used to help streamline the process of ...

  • conduct risk

    Conduct risk is the prospect of financial loss to an organization that is caused by the actions of an organization's ...

SearchSecurity

  • application whitelisting

    Application whitelisting is the practice of identifying applications that have been deemed safe for execution and restricting all...

  • security

    Security, in information technology (IT), is the defense of digital information and IT assets against internal and external, ...

  • insider threat

    An insider threat is a malicious hacker (also called a cracker or a black hat) who is an employee or officer of a business, ...

SearchHealthIT

  • HIPAA Privacy Rule

    The Standards for Privacy of Individually Identifiable Health Information, commonly known as the HIPAA Privacy Rule, establishes ...

  • HIPAA business associate agreement (BAA)

    Under the U.S. Health Insurance Portability and Accountability Act of 1996, a HIPAA business associate agreement (BAA) is a ...

  • telemedicine

    Telemedicine is the remote delivery of healthcare services, such as health assessments or consultations, over the ...

SearchDisasterRecovery

  • data recovery

    Data recovery restores data that has been lost, accidentally deleted, corrupted or made inaccessible. Learn how data recovery ...

  • disaster recovery plan (DRP)

    A company's disaster recovery policy is enhanced with a documented DR plan that formulates strategies, and outlines preparation ...

  • fault-tolerant

    Systems with integrated fault tolerance are designed to withstand multiple hardware failures to ensure continuous availability.

SearchStorage

  • data deduplication

    Deduplication retains one unique data instance to reduce storage and bandwidth consumed by remote backups, replication and ...

  • byte

    In most computer systems, a byte is a unit of data that is eight binary digits long. Bytes are often used to represent a ...

  • Secure Digital card (SD card)

    SD cards use flash memory to provide nonvolatile storage. They are more rugged than traditional storage media and are used in ...

SearchSolidStateStorage

  • flash file system

    Flash file systems are designed specifically for memory devices. A well-designed flash device and flash file system ensure ...

  • IOPS (input/output operations per second)

    IOPS measures the maximum number of reads and writes to non-contiguous storage. It is not an actual benchmark since vendor ...

  • eMMC (embedded MultiMediaCard)

    An embedded MultiMediaCard (eMMC) is a small storage device made up of NAND flash memory and a simple storage controller.

SearchCloudStorage

  • RESTful API

    A RESTful application program interface breaks down a transaction to create a series of small modules, each of which addresses an...

  • cloud storage infrastructure

    Cloud storage infrastructure is the hardware and software framework that supports the computing requirements of a private or ...

  • Zadara VPSA and ZIOS

    Zadara Storage provides block, file or object storage with varying levels of compute and capacity through its ZIOS and VPSA ...

Close