# momentum

- 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.
- 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.
- Philosophy. moment(def 7).

## Origin of momentum

## Examples from the Web for momenta

### Historical Examples of momenta

The change does not consist of these momenta, but is generated or produced by them as their effect.

The Critique of Pure ReasonImmanuel Kant

Again, if the values of the velocities and the momenta Reciprocal theorems.

On the other hand, what momenta of true religious thought have these ideals embraced?

The Religious SentimentDaniel G. Brinton

But there are still other momenta that go to make marriage difficult or impossible.

Woman under socialismAugust Bebel

It was only a momenta thread of timeon which hung the chance as to whether she would clear or not.

Within the CapesHoward Pyle

## momentum

- physics the product of a body's mass and its velocitySymbol: p See also angular momentum
- the impetus of a body resulting from its motion
- driving power or strength

## Word Origin for momentum

## Word Origin and History for momenta

## momentum

1690s, scientific use in mechanics, "quantity of motion of a moving body," from Latin momentum "movement, moving power" (see moment). Figurative use dates from 1782.

## momentum

- 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.

## momentum

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.)