This little girl is at equilibrium on her trampoline. Equilibrium is defined by"The state of a body or physical system that is at rest or in constant and unchanging motion. A system that is in equilibrium shows no tendency to alter over time. If a system is in static equilibrium, there are no net forces and no net torque in the system. If a system is in stable equilibrium, small disturbances to the system cause only a temporary change before it returns to its original state".

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