Browse Definitions:
Definition

angular acceleration (rotational acceleration)

Angular acceleration, also called rotational acceleration, is a quantitative expression of the change in angular velocity that a spinning object undergoes per unit time. It is a vector quantity, consisting of a magnitude component and either of two defined directions or senses.

The magnitude, or length, of the angular acceleration vector is directly proportional to the rate of change of angular velocity, and is measured in radian s per second squared (rad/s 2 or rad · s -2 ). Alternatively, the angular acceleration magnitude can be expressed in degrees per second squared (deg/s 2 or deg · s -2 ). The direction of the angular acceleration vector is perpendicular to the plane in which the rotation takes place. If the increase in angular velocity appears clockwise with respect to an observer, then the angular acceleration vector points away from the observer. If the increase in angular velocity appears counterclockwise, then the angular acceleration vector points toward the observer.

The angular acceleration vector does not necessarily point in the same direction as the angular velocity vector. Consider a car rolling forward along a highway at increasing speed. The angular acceleration vectors for all four tires point toward the left along the lines containing the wheel axles. If the car stops accelerating and maintains a constant velocity, the angular acceleration vectors disappear. If the car slows down going forward, the vectors reverse their directions, and point toward the right along the lines containing the wheel axles. If the car is put into reverse and increases velocity going backwards, the angular acceleration vectors point toward the right along the lines containing the axles. If the backward velocity is constant, the angular acceleration vectors vanish; if the backward velocity decreases, the angular acceleration vectors point toward the left along the lines containing the wheel axles.

Also see acceleration , radian per second squared , and degree per second squared .

This was last updated in January 2011

Join the conversation

4 comments

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.

fuck you
Cancel
me too thanks
Cancel
Can an observer inside a moving vehicle observe a change in direction of the vehicle given no outside reference and exclude forces acting on the observer?
Cancel
The answer given to my question is not answering my question; refer to my question before you answer, phew.
Cancel

-ADS BY GOOGLE

File Extensions and File Formats

SearchCompliance

  • internal audit (IA)

    An internal audit (IA) is an organizational initiative to monitor and analyze its own business operations in order to determine ...

  • pure risk (absolute risk)

    Pure risk, also called absolute risk, is a category of threat that is beyond human control and has only one possible outcome if ...

  • risk assessment

    Risk assessment is the identification of hazards that could negatively impact an organization's ability to conduct business.

SearchSecurity

  • security information and event management (SIEM)

    Security information and event management (SIEM) is an approach to security management that seeks to provide a holistic view of ...

  • polymorphic virus

    A polymorphic virus is a harmful, destructive or intrusive type of malware that can change or 'morph,' making it difficult to ...

  • cyberterrorism

    According to the U.S. Federal Bureau of Investigation, cyberterrorism is any 'premeditated, politically motivated attack against ...

SearchHealthIT

  • accountable care organization (ACO)

    An accountable care organization (ACO) is an association of hospitals, healthcare providers and insurers in which all parties ...

  • patient engagement

    Patient engagement is an ideal healthcare situation in which people are well-informed about -- and motivated to be involved -- in...

  • personal health record (PHR)

    A personal health record (PHR) is a collection of health-related information that is documented and maintained by the individual ...

SearchDisasterRecovery

  • business continuity and disaster recovery (BCDR)

    Business continuity and disaster recovery (BCDR) are closely related practices that describe an organization's preparation for ...

  • business continuity plan (BCP)

    A business continuity plan (BCP) is a document that consists of the critical information an organization needs to continue ...

  • call tree

    A call tree -- sometimes referred to as a phone tree -- is a telecommunications chain for notifying specific individuals of an ...

SearchStorage

SearchSolidStateStorage

  • hybrid hard disk drive (HDD)

    A hybrid hard disk drive is an electromechanical spinning hard disk that contains some amount of NAND Flash memory.

Close