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Physics

Period (Time Period)

Quick fact

The period of a pendulum depends only on its length and gravity, not on how far it swings – a property that made pendulum clocks reliable timekeepers.

Why this is interesting

Have you ever watched a pendulum swing back and forth, or noticed how the seasons repeat every year? Each of these cycles has a special duration called its 'period' – but what exactly defines it, and why does it stay constant?