# What are tides and how are they produced?

This is a few months old question and perhaps you have found or figured out the answer by now. However, it might be worth it to go a little deeper into it because the explanation is slightly more complex than what most people thinks.
We all know that the bulge, of a few centimeters up to several meters, that develops twice a day on the surface of the seas or oceans is due to the attraction of the Moon.
Not only do we know this, but we have known it for a long time. Dante, 300 years before Galilei and Newton, wrote that “Turning without rest, the Moon covers and discovers the sea shores”. The question that nobody asked in his days was : how could that be? Neither Dante nor Galilei had any notion of Gravity.
http://physics.stackexchange.com/
Galilei, who was more scientifically inclined than Dante, thought of the centrifugal force. The oceans had to be pushed outwards by the spinning Earth. It was not a bad idea and it lasted until Newton demonstrated the existence of the force of gravity: from then on, tides were due to the attraction of the mass of the Moon and that was it. Galilei was posthumously scorned and derided for centuries.
This was because the world did not know at the time a most relevant fact: the watery bulge as observed at certain hours of the day in Europe when the Moon is at Zenith position, concurs exactly, on the opposite side of the Earth, where the Moon is at Nadir position (see the picture).
How is that possible? The Moon and the bulge at opposite sides? Gravity could not explain such absurdity. Was Galilei right after all?… Well, partly. But for a big part.
In fact three factors (at least) concur in creating tides and the Moon’s Nadir bulge. One is gravitational, and two are centrifugal.
1) Gravitational: the Moon’s pull on the Earth diminishes with the inverse cube of the distance. While the Zenith bulge is obvious, the Nadir side of the needs some explaining. Relative to the Moon, it is further away (twice the Earth’s radius) from its satellite than the Zenith side is. This represents nearly 3.5% of the total average Earth-Moon distance which, to the denominator and to the power 3, is a sizable figure.
In other words, the Nadir side of the Earth with respect to the Moon is pulled less energetically inwards, than the Zenith side is pulled outwards. The former is therefore actually “left behind” with respect to the latter that is pulled up. The water surface is accordingly deformed. Hence the Nadir bulge
.
2) Centrifugal 1 : this is simply what Galilei thought, the away push of the week water surface due to the rotation of the Earth (The Coriolis force is another such effect). However if you do the math, which I didn’t, this is rather a small number.
3) Centrifugal 2. It is the most important one and I left it for the end. Here is the scoop: the Moon does not only revolve around the Earth; they also both revolve around each other (the Moon moving considerably faster) and the couple system is centered about a point in space located on the plane of the ecliptic closer to the Earth.
That is to say: Earth and Moon form a rotating couple whose gravity centre sits between the two. The rotational arm of such couple is therefore not just the Earth’s radius, but a stretched arm at least 20 times longer; the total distance between Earth and Moon being of approx. 500.000 km.
Hence its ensuing centrifugal force acting on either side of the Earth is much, much stronger than mere gravity would suggest. Again I didn’t, and do not intend to do the math.
The resulting outward push on the water surface, Zenith and Nadir bulges, are therefore the result of all three forces: one pulling and two outward pushing in opposite directions.
I made this answer a little longer than I wanted to, but I had an old and respectable countryman to vindicate.

Don't use plagiarized sources. Get Your Custom Essay on
What are tides and how are they produced?
Just from \$13/Page
Calculate the price
Pages (550 words)
\$0.00
*Price with a welcome 15% discount applied.
Pro tip: If you want to save more money and pay the lowest price, you need to set a more extended deadline.
We know how difficult it is to be a student these days. That's why our prices are one of the most affordable on the market, and there are no hidden fees.

Instead, we offer bonuses, discounts, and free services to make your experience outstanding.
How it works
Receive a 100% original paper that will pass Turnitin from a top essay writing service
step 1
Fill out the order form and provide paper details. You can even attach screenshots or add additional instructions later. If something is not clear or missing, the writer will contact you for clarification.
Pro service tips
How to get the most out of your experience with Homework Mules
One writer throughout the entire course
If you like the writer, you can hire them again. Just copy & paste their ID on the order form ("Preferred Writer's ID" field). This way, your vocabulary will be uniform, and the writer will be aware of your needs.
The same paper from different writers
You can order essay or any other work from two different writers to choose the best one or give another version to a friend. This can be done through the add-on "Same paper from another writer."
Copy of sources used by the writer
Our college essay writers work with ScienceDirect and other databases. They can send you articles or materials used in PDF or through screenshots. Just tick the "Copy of sources" field on the order form.
Testimonials
See why 20k+ students have chosen us as their sole writing assistance provider
Check out the latest reviews and opinions submitted by real customers worldwide and make an informed decision.
Psychology
Thank you. I will forward critique once I receive it.
Customer 452467, July 25th, 2020
Education
Thank you so much, Reaserch writer. you are so helpfull. I appreciate all the hard works. See you.
Customer 452701, February 12th, 2023
Political science
Thank you!
Customer 452701, February 12th, 2023
Great paper thanks!
Customer 452543, January 23rd, 2023
Psychology
I requested a revision and it was returned in less than 24 hours. Great job!
Customer 452467, November 15th, 2020
Accounting
Thank you for your help. I made a few minor adjustments to the paper but overall it was good.
Customer 452591, November 11th, 2021
Political science
I like the way it is organized, summarizes the main point, and compare the two articles. Thank you!
Customer 452701, February 12th, 2023
Technology
Customer 452551, October 22nd, 2021
Finance
Thank you very much!! I should definitely pass my class now. I appreciate you!!
Customer 452591, June 18th, 2022
11,595
Customer reviews in total
96%
Current satisfaction rate
3 pages
Average paper length
37%
Customers referred by a friend