vuorovesivoimaa

Vuorovesivoimaa, known in English as tidal force, is a gravitational effect that arises from the difference in gravitational pull on opposite sides of an object. This phenomenon is most commonly observed in the context of the Earth's oceans, causing the tides. The Moon's gravitational pull is stronger on the side of the Earth facing it than on the opposite side. This differential force stretches the Earth slightly. Similarly, the Sun exerts a tidal force on the Earth, though it is weaker than the Moon's due to its greater distance.

The Earth orbits the center of mass of the Earth-Moon system. Because of this orbit, even the side of the Earth facing away from the Moon experiences an outward inertial force that, combined with the weaker gravitational pull from the Moon on that side, creates a bulge in the oceans. These bulges, one facing the Moon and another on the opposite side, are the primary cause of high tides. As the Earth rotates, different parts of the planet pass through these bulges, resulting in the cyclic rise and fall of sea levels. The Sun's gravitational influence also contributes to tides, leading to spring tides when the Sun, Earth, and Moon are aligned, and neap tides when they are at right angles.