Something else about tides
There is a force known as the tidal force, and it occurs since the gravity force gets weaker while things are separated by greater distances. This difference in the distance also makes a difference in the gravitational attraction among two points, making the closer region higher and the opposite region lower. That is the reason why the tidal force “faint” too fast, but is stronger when the distance between the involved bodies is short.
For instance, in the case of the Earth and the Moon, we say that its distance is, on average, 384,000 km. However, that is measured from the Earth’s core to the Moon’s core. If we measure from the surface (without counting the distance between the center and the last mentioned), the Moon is 6700 km closer, whereas who is on the other side of the Moon is 6700 km further regarding the center of the Earth.
As we have seen, both gravity and tidal force decrease according to the distance. For example, if we increase the distance between two objects twice, the gravity force slows down four times, rather the tidal force does the eighth part. If we increase the distance five times between these objects, gravity decreases 25 times, but the tidal force does 125 times!
Then, we can confirm that the gravity force drops with the distance squared, whereas the tidal force does with the distance cubed. For that reason, the region of the Earth that is straight towards the Moon is under more attraction, the regions in the middle are under a “neutral” force, and the further region is under less attraction. For that very reason, high tides occur in the region that directly faces the Moon and, in the opposite-in-diameter part.
It is essential to have in mind that the tidal force is related to gravity, and it is a consequence of gravity acting on sized objects.
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