Does the gravity of the moon and the Earth combine?

Question

Ie if you were on the opposite side of the Earth from the moon, is the gravity higher than if you stand on the side of the Earth closest to the moon?
+ Are the masses of the Earth and the moon effectivly 'combined' when 'far off' object are concerned?

Answer 1

Yes. If you think of a situation in which you start very far away from the earth and moon, they would appear as a single point, and you could calculate their combines gravitational effect on you in terms of their combined mass as though it were all at a point between them.

As you get closer to them though, this approximation gets worse and worse, and you have to start treating them as separate masses.

Once you are on the earth, you have to treat them separately (obviously), and yes, there is slightly less gravity when the moon is directly above you than when it is on the other side of the earth. There isn't much difference though since it is comparatively small and far off, but liquids are distorted by the difference, which gives us tides.

Answer 2

First, the earth is a more massive entity and thus has a greater influence on the moon than it does on us. If they were closer to eachother, at a certain closeness the moon's velocity would no longer be enough to escape Earth's gravity... so instead of orbiting as a satellite, they would colllide. However, if they were closer, but not THAT close, then the current influence of moon's gravity on earth processes (i.e. tide/waves, etc.) would be increased. Hope this answered your question(s).

Answer 3

On Earth, the effect of gravity on your body is slightly stronger at the ocean bottom compared to the top of Mt. Everest. This is because on the ocean bottom, you are closer to the actual center of the Earth, where gravity is the strongest.

The gravity between the Earth and Moon is determined by the mass of each and the distance between them. The same goes for the effect of the Moon's gravity on you. The closer you are to the Moon, the stronger the pull of gravity.

Of course we don't actually feel these differences in gravity because of our minute size compared to that of the Earth and Moon.

The effect of the sun's gravity on a far off object, say the Moon, is completely independent from the effect of its gravity on the Earth. The force is greater between the sun and Earth based on mass. The effect of Earth's gravity of the Moon is greater than the sun's because of the relative distance between the Earth and Moon.

Answer 4

No, they don't combine but, its the eath's gravity that keeps the moon in orbit around it.

The oceans at the equator rise and fall with the moon's phases which causes the tides around the world. If you stood at the equator directly under the moon, you would probably be a fraction lighter due to the moon's pull.

It's all conjecture.

Answer 5

This has happened, more than once, millions of years ago. When the land bridge near Gibraltar blocked off the Mediterranean basin. When it broke, there was the mother of all waterfalls, and the basin took hundreds of years to fill up.
Each time it dried up, it left vast deposits of salt , which are still there. The last time it happened was about six million years ago. The canyons created by the rivers flowing into the basin when it was dry can still be traced!
Fascinating stuff.

Answer 6

no they dont.. if they did, it would be called a binary system where two things orbit around each other. Gravity doesnt combine, and no matter where the moon is the force of gravity on an object will be the same.

Answer 7

No they don't combine but the moon does have and effect on earth it keeps it anchored. With out the moon we would be spining crazily. LIke we wouldn't be rotating on an axis as we do.

Answer 8

Sorta. every action has an equal and opposite reaction so they are all accounted for, both in the physical world and when we need to do the math that goes with it. The mass of both objects is always considered.

Answer 9

the gravitation of the moon gives us the tides when the sun & moon are in line we get spring tides & neep tides when the moon is on its own

Answer 10

.It seems to me that that you think that you have come up with something that no one thought of. As far as far off objects are concerned, we are NOTHING.The distances are so vast , that a question such as yours should be of any significance is wholly insignificant. Sorry that is the way it is. You have to understand the whole before you can consider the individual.