What is the tide?


What is the tide?

In: Physics

The rocking motion in the ocean that results from the gravitational pull of the forces that exist between the sun and the moon.

The tide is the moon pulling on earth’s oceans.

The moon may be smaller than earth and a quarter million miles away, but while we don’t feel the effects of its gravity, the sloshing liquid of the ocean does.

Enough to give a bit of a tug on the water.

Here’s a pretty good gif to show it.


Essentially as the earth spins, the side of the earth closest to the moon and the part furthest away experience high tide, then as the earth keeps spinning those areas start working towards low tides.

You can get extremely high and extremely low tides at certain points in the moons orbit when it and the sun both stack their gravity together to influence our oceans.

The force of gravity varies with distance. So, e.g. the part of the Earth closest to the Moon is pulled harder than the center of the Earth, which is pulled harder than the part farthest from the Moon. So the Earth experiences a slight stretching along the line from Earth to Moon.

But the Earth is rotating much faster than the Moon is going around the Earth, which means that about 6 hours later, the parts that were at extreme distances are now at middling distances, and the stretching is relaxed. And then 6 hours later still, they’re at extreme distances again. So there’s this continual sloshing, as ocean water rises and falls, even more than the rock underneath rises and falls.