Galileo1 - moving objects appear to be deflected to the...

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Galileo Galileo's studies of how forces operate also provide the foundation to prove that Earth spins on its axis. Although the stars and Sun appear to rise and set every night or day, they are actually stationary. Evidence of the Earth's rotation (from west to east) is seen with the deflection of objects moving in north-south direction caused by the differences in the linear speed of the rotation at different latitudes. All parts of the Earth take 23 hours 56 minutes to turn once, but the higher latitudes are closer to the Earth's rotation axis, so they do not need to rotate as fast as regions nearer the equator. A moving object's west-east speed will stay at the original value it had at the start of its motion (unless some force changes it). If the object is also changing latitudes, then its west-east speed will be different than that for the part of the Earth it is over. Therefore,
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Unformatted text preview: moving objects appear to be deflected to the right in the northern hemisphere and to the left in the southern hemisphere. This is called the coriolis effect after Gustave-Gaspard Coriolis (lived 1792--1843 C.E.) who deduced the effect in 1835 to explain why cannonballs shot long distances kept missing their target if the cannon was aimed directly at its target. See energy flow section for applications (and illustrations) of the coriolis effect to planet atmospheres. Jean-Bernard-Lon Foucault (lived 1819--1868) gave the first laboratory demonstration of the Earth's spin in 1851. A large mass suspended from a long wire mounted so that its perpendicular plane of swing is not confined to a particular direction, will rotate in relation to the Earth's surface. The only forces acting on the ball are gravity and the wire tension and they lie in the plane of oscillation....
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