System of 4 Pendulums: Why Don't They Move Faster?

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SUMMARY

The discussion centers on the dynamics of a system of four identical mass pendulums and the principles of momentum and energy conservation during collisions. It is established that when two pendulums are raised and released, they do not move with double the speed of a single pendulum due to the constraints of conservation laws. Specifically, the conservation of momentum and energy cannot be satisfied simultaneously if only one pendulum moves after a collision, as demonstrated by the equations 2v = u for momentum and u² = 2v² for energy. This leads to the conclusion that the system's behavior adheres strictly to these physical laws.

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teken894
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In a system of 4 same-mass pendulums, when give potential energy to a pendulum (by raising it) and letting go, one pendulum on the other side moves equally...

When two are raised and let go, two pendulums will move after the collision...

why doesn't one pendulum move with twice the speed, rather than two pendulums moving?

Isn't it that two pendulums moving slower is the same as one pendulum moving faster?Hope I have made my wording sufficiently clear...

pendulum.gif


That's the kind of system I'm referring to
 
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It is not possible to conserve both momentum and energy if only one mass moves after the collision.

Suppose the two masses arrive with speed v and the single mass leaves with speed u. Then momentum conservation requires 2v = u but energy conservation requires [itex]u^2 = 2 v^2[/itex] which is possible only if v = 0 or 1 = 2.
 

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