mpc755 writes:
Is there a contradiction with saying the Sun interacts with the Earth-Moon system as a single entity, but will still have an effect on the Earth's tides? If the sun can still impact the Earth's tides, then isn't it interacting with the Earth as a single entity?
And here you've stumbled into another very common misconception, even among science enthusiasts and many physics students.
First of all, it's our moon that causes earth's tides more than anything else. The misconception is that the moon's gravity itself somehow pulls on the water of the oceans and causing them to rise. Ask anyone here among the science enthusiasts and they will tell you the same thing. This is not entirely correct.
To fully understand why we have tides, you first need to have a little imagination to understand what I'm about to explain.
The earth's tides are not caused by the direct gravitational pull of the moon on earth's ocean waters. Think of it this way. You don't feel any lighter everytime the moon passes over your head, do you? The moon's gravity acts on earth more or less as a whole rather than the individual objects.
The true explanation for earth's tides is the following. Even though we tend to think of gravitational force acting on an object like earth more or less as a whole, we have to put into account the distance between one side of the earth to the moon and the other side of the earth to the moon. The fact is the side of the earth that is closer to the moon experiences a slightly greater pull from the moon than the other side. The effect of it is the earth's shape changes back and forth very slightly. The changes in shape are so minutely slight that you can't actually observe any difference here on earth. But this changes in shape actually cause the earth's oceans to appear to rise up and down.
Here is something you can do to help you better visualize this effect. Get a plastic container like a milk bottle or something. Pour water into it. Now, compress it and release it. Observe how the water wobbles back and forth.
This same effect is what is causing one of Jupiter's moons to have active volcanos. Jupiter's gravity is doing the same thing to its moon what earth's moon is doing to earth but at a much greater scale. The changes in the shape of jupiter's moon is causing a lot of friction within the moon which in turn is giving it a very active core.
Anyway, if my above explanation doesn't make any sense, I guess it's fine if you want to continue to believe that the moon is actually pulling onto the earth's ocean water and causing it to rise giving us tides.
Disclaimer:
Occasionally, owing to the deficiency of the English language, I have used he/him/his meaning he or she/him or her/his or her in order to avoid awkwardness of style.
He, him, and his are not intended as exclusively masculine pronouns. They may refer to either sex or to both sexes!
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