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Galileo's Battle for the Heavens

His Experiments

 

Galileo homepage

Falling Objects | Projectiles | Inclined Planes | Pendulums

In this formula, S = the number of swings, l = pendulum length, and C = a constant number.

Table of pendulum formula, s^2 x l = C, for short, med, long pendulums

In the time it takes the 1-ft pendulum to cycle 30 times, the 2.25-ft pendulum should have cycled about 20 times and the 9-ft pendulum cycles 10 times.

Galileo found the same pattern with experiments he conducted. This pattern revealed that the square of a pendulum's period varies directly with its length.

The formula above shows this relationship. The "S" represents the number of swings in a given amount of time. (For this experiment, S equals the number of cycles that the 2.25- and 9-ft pendulums can complete during the time it takes the 1-ft pendulum to cycle 30 times. )

With this virtual experiment, we've set it up so that the numbers work out exactly how the formula says they should, but if you dig out some string and weights and try the experiment out for yourself, you should see that it works just as well in real life.

That wraps up the Pendulum experiment. If you haven't already done so, check out one of the other Galileo experiments.







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