Conservation of momentum in perfect elastic collisions

AI Thread Summary
Momentum conservation is inherently vectorial, while perfect elastic collisions utilize scalar conservation for simplicity in calculations. This distinction arises because momentum, being a vector, must account for direction, whereas energy conservation in elastic collisions is expressed as a scalar quantity. The necessity of scalar conservation in elastic collisions simplifies the analysis of energy transfer, despite momentum remaining conserved in all types of collisions. Understanding this difference clarifies the application of conservation laws in physics. Thus, both momentum and energy conservation principles are crucial, but they serve different roles in collision analysis.
anachin6000
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I learned that momentum conservation is vectorial, and now, when i read about perfect elastic collisions, I can't understand why they use a scalar conservation. I tryed to use vectorial coervation to see the diference and it's true: it's needed a scalar conservation. But why?
 
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Momentum is a vector and is always conserved, whether the collision is elastic, inelastic, somewhere in-between.
Energy is a scalar and is conserved only in an elastic collision.
 
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