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Reason for Two TidesTides are caused not simply by gravity but by the gravity gradient or in other words the difference in gravity in different places. The side of the earth that is closer to the moon is more strongly accelerated than the side that's far away. The water that's near the moon gets pulled toward it (that's obvious). The not so obvious part is that the water on the far side is getting "left behind" because the Earth is getting pulled away from it.

The phenomenon of tidal force gets really significant around things with stronger gravitational pulls, say a black hole. If you tried flying into a black hole you'd never make it. The front of your ship would get pulled in faster than the back, ripping it apart before you arrived.

Same as above with a different 'spin'.When I got the following idea, I got the "high tide" opposite the moon. For a moment, in your mind, imagine that the earth and the moon are exactly the same size and mass. Which one is orbiting around the other? In fact, they would each be orbiting around a point in space right between them. Looking from high above in space, we'd see them both basically spiraling around one another. This should be obvious, since there would be absolutely no reason why one of them should (or could) be more 'stationary' than than the other.

The above idea holds true now for the real earth and moon, even though the moon is smaller. We would observe some perturbation, or scalloping of earth's orbit around the sun because of the moon's presence, and we would see the same kind of thing if we observed the moon's "orbit" around the sun.

What about that theoretical "point" around which they both orbit? Interestingly, the "point" is within the body of the earth. And, of course, the point is constantly moving, as the earth rotates on its axis. So, in a sense, whatever part of the earth's surface is opposite the moon, is in fact swinging out behind the moon-side surface of the earth! Thus, the push outward of the tides on the side opposite the moon. This is happening as a continuous movement as the earth rotates and the moon orbits. You can imagine in your mind's eye that there are therefore 2 high tides and two low tides on the planet, at any given point in time. Since we rotate through all of that "tugging and pulling" in 24 hours, we experience all of those tides.

The rotation of the earth is so much faster than the moon's orbit (relatively speaking) that the rotation has the effect of dragging the tide along with it a little, in advance of the moon, which has some interesting effects beyond the scope of this answer.

Another Viewpoint: So that's two different explanations. The first is based on

"differential gravity" and the second is based on "centrifugal" effects. Unfortunately, there are several "explanations" you can find for this tidal

phenomenon. Even scientists can give different answers. I tend to believe what mathematicians say about this question. From my reading on the subject, I believe that "differential gravity" is the preferred explanation when the problem is analysed mathematically.

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โˆ™ 2013-03-01 00:42:01
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Q: Why are there two high tides in one day?
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Related questions

How many times a day do high tides occur?

There are two high tides and two low tides a day.

Are there two high tides in the same location in one day?


Why are high and low tides in two consecutive days?

Actually, there are TWO high tides and TWO low tides, on almost every day.

What are two high tides and two low tides a day called?

That's called diurnal tides.

How many tides are there during the night?

in the night whe have two tides in total is 4 two low tides in the day and two high tides in the night

What tidal pattern has two high tides and two low tides each day?


Which tidal pattern has two high tides and two low tides each day?


What are the names of the different types of tides?

The three types of tides are:DiurnalSemi-diurnalMixedDiurnal tides have one high and one low tides per day.Semi-diurnal tides have two high and two low tides per day.Mixed tides go from extreme high to extreme low, then medium high and then medium low.Here is the distribution of the different tides

High tides usually occur twice each?

Most areas of the ocean have two high tides and two low tides a day (semidiurnal tide).

How many high tides are there per day?

Two high tides occur each day, due to the gravitational pull on the ocean generated by the moon. There are also two low tides in every 24-hour period.

How many times does the ocean level reach high or low tide?

two high tides and two low tides per day

What is the lunar phase on the high and low tide days?

There are two high tides and two low tides every day.

Occurrence of high and low tide in a day?

Generally, two high tides and two low tides per 24-hour period.

How many times in a day do tides usually occur on the Texas coast?

Two high tides and two low tides altogether four

Does every location on earth have two high tides a month?

No! They have 2 tides a DAY!!

What are the two of tides?

Low tides and high tides. they both come twice a day. the moon determens the tide.

How many high tides are there each day?

Two Each Day

How many high tides per day?

Two per day

What would happen to the tides if the earth rotated twice as fast on its axis?

there would be two low tides and two high tides per day

How many high and low tides do most coastal areas experience in one day?

Two of each.

How many high tides happen at a given coast at any 24 hour period?

One to two, depending on the day.

When are ocean tides experienced most?

Tides may be semidiurnal (two high waters and two low waters each day), or diurnal (one tidal cycle per day). In most locations, tides are semidiurnal. Because of the diurnalcontribution, there is a difference in height (the daily inequality) between the two high waters on a given day. Some of the greatest differences between high and low tides re found in the Bay of Fundy (eastern Canada).

What is two high tides and two low tides a day called?

Find the answer at Message MandoCommando about it

Why is there are usually two high tides and two low tides each day?

It's controlled by the moon's magnetic pull.

How many types a day does high tide occur each day?

Tides can be semidiurnal with two high waters and two low waters each day , or diurnal which is one tidal cycle per day. Most are semdiurnal. ou can search for a tide chart on line to see what tides occur around the world.