16 lines
544 B
Markdown
16 lines
544 B
Markdown
[[Linear Momentum]]
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Total momentum of system stays the same when there is no external force acting on it.
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# Summary
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* Total momentum is vector sum
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* If net external force is 0, then momentum stays the same.
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* Momentum is conserved in every action
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* Nonzero net external force transfers momentum in or out of system, which is impulse.
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* Center of mass velocity stays constant when no external force.
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# Center of Mass Velocity
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$$\vec v_{cm}=\frac{\Sigma \vec p_i}{\Sigma m_i}$$
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Treats whole system like momentum is concentrated in one point.
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