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Physics

Viscous Damping

Quick fact

Viscous damping is the principle behind why a pendulum in air eventually stops swinging, yet the same pendulum in a vacuum would continue much longer—the air provides a velocity-dependent resistance.

Why this is interesting

You’ve felt it when a car’s shock absorber smooths a bump or when a door closer gently stops a swing. What hidden force turns bouncy motion into a gentle settle?