The book of science

Tom Sharp

Galileo Galilei kinematics


Disregarding authority


Galileo did not get everything right. He thought that the tides were not related to the moon, as Johannes Kepler had claimed, and he misinterpreted the rings of Saturn. In his defense, one must realize that his best telescope magnified the size of objects only 30 times.

Because falling objects moved too fast to accurately time, instead of dropping metal balls from the Tower of Pisa, Galileo studied pendulums and bronze balls rolling down inclined grooves. He timed these by collecting water released from a reservoir and carefully weighing it.

Isaac Newton incorporated Galileo’s law of horizontal motion, the principle of inertia, into his first law of motion.

Although Christiaan Huygens is credited with inventing the pendulum clock in the 1650s, Galileo realized that a pendulum would provide a more accurate clock and invented an escapement mechanism for it in 1642.

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