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Galileo's Battle for the Heavens

His Experiments

 

Galileo homepage

Falling Objects | Projectiles | Inclined Planes | Pendulums

Diagram: three pendulums

That's right. Experiments with our virtual pendulum (and with real pendulums) show that changing neither the weight nor the release height affects its period. Changing the length of the pendulum, however, does affect how fast it moves back and forth. This is how a pendulum clock's speed is altered if it's running too fast or too slow. Take a look at a pendulum clock, and you'll notice that its rate is adjusted by moving the pendulum's bob higher or lower.

Next, see exactly how a pendulum's period is affected by its length...







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