Physics' insights into pedestrian motion and crowd dynamics: reply to comments on "The emergence of design in

Antonio F Miguel1

  • 1Department of Physics, Evora University, Rua Romão Ramalho 59, 7000-671 Evora, Portugal. afm@uevora.pt

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Recall that a particle in equilibrium is one for which the external forces are balanced. Static equilibrium involves objects at rest, and dynamic equilibrium involves objects in motion without acceleration; but it is important to remember that these conditions are relative. For instance, an object may be at rest when viewed from one frame of reference, but that same object would appear to be in motion when viewed by someone moving at a constant velocity.
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Energy Diagrams - I01:14

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