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Does anything else other than the moon control the tides? Does a certain life force live that controls the tides but makes it seem like the moon? Can another life force control the tides?
Question Date: 2015-08-26
Answer 1:

The sun also raises tides on the earth. In fact, the solar induced tide is about 40% of the total. The moon is the other player. There really is no life force involved; basically we can understand how tides get raised by considering two bodies. Let us say the earth and the moon in isolation. Now when these bodies are very, very far away, we can condor that the mass of earth is acting like a point mass at the center and the same for the moon. In this case the tidal force is very small.....basically negligible. Now imaging the situation when we move the moon closer to the earth. Note now that one side of Earth is significantly closer to the center of the moon compared to the point on the other side of the earth. The tidal force is actually the DIFFERENCE in the force exerted between the sub lunar point and the point across the diameter of Earth.

That is what the tidal force is... it is a differential gravitational force.

Answer 2:

ANYTHING with mass (and thus gravity) causes tides. You cause tides with the mass from your body.

The moon exerts the strongest tide-inducing force on the earth because it is relatively massive and relatively close-by, and the strength of tidal forces caused by an object increases with the mass of the object and even faster with the closeness of the object. The sun is also important in causing tides, although not as much as the moon because the sun is so much farther away than the moon, even though it is much more massive.

All of the living things on Earth together add up to a tiny amount of mass in comparison to the mass of the earth itself. This means that while, technically, the bodies of living things exert tidal forces just like everything else, these forces are so small that they are completely overwhelmed by the mass of nonliving objects, such as the moon, Sun, Jupiter, etc.

Answer 3:

The Sun also affects the tides on Earth. Both the Moon and Sun have a gravitational force that "pulls" on the Earth. This "pulling" force causes the Earth's oceans to bulge on one side or another, forming the tides.

When we see a "new" or a "full" Moon, the gravitational force from the Sun adds to the force from the Moon, producing our largest tidal ranges called Spring Tides. During a "quarter" Moon, the gravitational force from the Sun subtracts from the force from the Moon, producing small tidal ranges called Neap Tides.

Waves, however, are not related to tides and, instead, are caused by other things on Earth. For example, when wind blows across the ocean surface, waves can form. If the wind blows faster, the waves become larger. Extremely large waves can be made by a landslide that drops into the ocean or by an earthquake that occurs near the bottom of the sea. These extremely large waves are called tsunami. Large mammals, like whales, can make large splashes in the ocean, but these splashes are never big enough to become tsunami. Tsunami are not related to tides either.

The only things that can create tides are big objects in space: moons, planets, and stars. No life forms are big enough to generate gravitational forces that "pull" on the ocean to make tides.

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