momentum

[moh-men-tuhm]
noun, plural momenta [moh-men-tuh] , momentums.
1.
force or speed of movement; impetus, as of a physical object or course of events: The car gained momentum going downhill. Her career lost momentum after two unsuccessful films.
2.
Also called linear momentum. Mechanics. a quantity expressing the motion of a body or system, equal to the product of the mass of a body and its velocity, and for a system equal to the vector sum of the products of mass and velocity of each particle in the system.
3.
Philosophy, moment ( def 7 ).

Origin:
1690–1700; < Latin mōmentum; see moment

memento, momentum.
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World English Dictionary
momentum (məʊˈmɛntəm)
 
n , pl -ta, -tums
1.  physics See also angular momentum p the product of a body's mass and its velocity
2.  the impetus of a body resulting from its motion
3.  driving power or strength
 
[C17: from Latin: movement; see moment]

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Etymonline
Word Origin & History

momentum
1699, "quantity of motion of a moving body," from L. momentum "movement, moving power" (see moment). Fig. use dates from 1782.
Online Etymology Dictionary, © 2010 Douglas Harper
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American Heritage
Science Dictionary
momentum  [%PREMIUM_LINK%]     (mō-měn'təm)  Pronunciation Key 
Plural momenta or momentums
A vector quantity that expresses the relation of the velocity of a body, wave, field, or other physical system, to its energy. The direction of the momentum of a single object indicates the direction of its motion. Momentum is a conserved quantity (it remains constant unless acted upon by an outside force), and is related by Noether's theorem to translational invariance. In classical mechanics, momentum is defined as mass times velocity. The theory of Special Relativity uses the concept of relativistic mass. The momentum of photons, which are massless, is equal to their energy divided by the speed of light. In quantum mechanics, momentum more generally refers to a mathematical operator applied to the wave equation describing a physical system and corresponding to an observable; solutions to the equation using this operator provide the vector quantity traditionally called momentum. In all of these applications, momentum is sometimes called linear momentum. See also angular momentum, impulse.

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Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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American Heritage
Cultural Dictionary

momentum definition


In physics, the property or tendency of a moving object to continue moving. For an object moving in a line, the momentum is the mass of the object multiplied by its velocity (linear momentum); thus, a slowly moving, very massive body and a rapidly moving, light body can have the same momentum. (See Newton's laws of motion.)

Note: Figuratively, momentum can refer to the tendency of a person or group to repeat recent success: “The Bears definitely have momentum after scoring those last two touchdowns.”
The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Encyclopedia Britannica
Encyclopedia

momentum

product of the mass of a particle and its velocity. Momentum is a vector quantity; i.e., it has both magnitude and direction. Isaac Newton's second law of motion states that the time rate of change of momentum is equal to the force acting on the particle. See Newton's laws of motion.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Example sentences
The law of conservation of momentum--a profound physical law--governs the
  motion of colliding objects.
This rotation can be described as angular momentum, a conserved measure of its
  motion that cannot change.
It has more momentum than you would expect for its velocity.
As the cloud collapses, both its mass and angular momentum remain constant.
Image for momentum
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