# conservation of momentum

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Related to conservation of momentum: Conservation of Angular Momentum

## Conservation of momentum

The principle that, when a system of masses is subject only to forces that masses of the system exert on one another, the total vector momentum of the system is constant. Since vector momentum is conserved, in problems involving more than one dimension the component of momentum in any direction will remain constant. The principle of conservation of momentum holds generally and is applicable in all fields of physics. In particular, momentum is conserved even if the particles of a system exert forces on one another or if the total mechanical energy is not conserved. Use of the principle of conservation of momentum is fundamental in the solution of collision problems. *See* Collision (physics), Momentum

## conservation of momentum

The principle that in any system of interacting bodies the total linear momentum in a fixed direction is constant provided that there is no external force acting on the system in that direction. The angular momentum of a system of bodies rotating and/or revolving about a fixed axis is also conserved provided that no external torque is applied.## conservation of momentum

[‚kän·sər′vā·shən əv mə′mən·təm] (mechanics)

The principle that, when a system of masses is subject only to internal forces that masses of the system exert on one another, the total vector momentum of the system is constant; no violation of this principle has been found. Also known as momentum conservation.