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You're right that the energy comes from the Moon-Earth system (at least for the lunar tides). The Moon is slowing down ever so slightly, and moving away from the Earth (to maintain angular momentum). The Earth's rotation is also slowing (day is getting longer). In a few billion years the day will be longer than the month, and the Moon will start falling towards the Earth.
Sounds very true. But can you put it in real numbers? Move so much water all the time, few years should be enough to change the orbit a lot.
Fish chase warm water, may help a bit on tide.
Look back, science always follow mainstream scientists believes.
Look around, so so so so.
Because energy is defined as the ability to do work on objects..
Of all the physical concepts, that of energy is perhaps the most far-reaching. Everyone, whether a scientist or not, has an awareness of energy and what it means. Energy is what we have to pay for in order to get things done. The word itself may remain in the background, but we recognize that each gallon of gasoline, each Btu of heating gas, each kilowatt-hour of electricity, each car battery, the wherewithal for doing what we call work. We do not think in terms of paying for force, or acceleration, or momentum. Energy is the universal currency that exists in apparently countless denominations. The above remarks do not really define energy. No matter. It is worth recalling once more the opinion that H.A. Krammers expressed: “The most important and fruitful concepts are those to which it is impossible to attach a well-defined meaning.” The clue to the immense value of energy as a concept lies in its transformation. It is conserved – that is the point. Although we may not be able to define energy in general, that does not mean that it is only a vague, qualitative idea. We have set up quantitative measures of various specific kinds of energy: gravitational, electrical, magnetic, elastic, kinetic, and so on. And whenever a situation has arisen in which it seemed that energy disappeared, it has always been possible to recognize and define a new form of energy that permits us to save the conservation law. And conservation laws, as we remarked at the beginning of Chapter 9, represent one of the physicist’s most powerful tools for organizing his description of nature.
To further clarify matters, I should really give you a precise definition of energy. Unfortunately, I can't do this. Energy is the most fundamental dynamical concept in all of physics, and for this reason, I can't tell you what it is in terms of something more fundamental. I can, however, list the various forms of energy - kinetic, electrostatic, gravitational, chemical, nuclear - and add the statement that, while energy can often be converted from one form to another, the total amount of energy in the universe never changes. This is the famous law of conservation of energy. I sometimes picture energy as a perfectly indestructible (and unmakable) fluid, which moves about from place to place but whose total never changes. (This image is convenient but wrong - there simply isn't any such fluid).
If gravity is constantly providing the energy for the moon’s acceleration, why is gravity not becoming weaker?
Where does the energy come from ? The initial rotational energy was in the gaseous cloud from which the solar system condensed which had a degree of rotation relative to the rest of the universe.See Mach, Einstein, Newton, ether etc rotational energy is a big puzzle
Surely all the energy originated from whatever existed before the big bang.
If this was a singularity this implies that black holes can explode.
Before we surely understand why is electron not stick to proton, we are nice talkers.
We have not find +1 charge yet. We have +2/3, -1/3 and -1 charges.How you explain?
Every time a see the word quantum, I want to run, like now.
Why can't we build a power plant use gravity like the sea does if gravity causes tide?
You cannot do anything in the UK that impacts on wild life we would rather get our electricity from coal burning plants than have some sand eels or wading birds inconvenienced.
Hmmm... So the tides are pushing the moon (7.3 × 1022 kg) away by about 3.8cm a year.That seems like quite a bit to me.Say the area of the oceans are about (510,066,000 sq km)What is the average height of the tides, maybe 2 meters, although perhaps one should think of half of it being raised, and half lowered. Are polar tides less?So, for moving: 5.1 × 108 km2 x (1m depth) x (1000m/km)2 x 1000 dm3/m3 = 5.1 × 1017 kg of water moved by the tides twice a day.So, 5.1 × 1017 kg * 365 * 2 = 3.7 × 1020 kg of water raised by about 1m per year.So...The moon weighs about 100x the annual tides.And the orbit is pushed out by about 1/100 the depth of the tides.There are probably many different ways to do the calculation. Perhaps it would be better to calculate velocity and momentum changes of the moon equivalent to the 3.8 cm change in the orbit. But, my quick estimate for the amount of water in the tides came quite close to the orbital change. Did you do any calculations to indicate it isn't possible, or did you just conclude that there is a lot of water sloshing around in the oceans?
F=ma, V=at. The moon pushed away by tidal force for so long, it should be away way faster by now.
S=vt, t=5 billion years, how far away should be the moon now? If tidal force came from gravity.
The a is always there, the v is increasing with t and not constant. Your ballpark is huge.
Quote from: jccc on 20/01/2015 20:51:37The a is always there, the v is increasing with t and not constant. Your ballpark is huge.The orbital velocity decreases with time. Leave it to the physicists to write a program calculating where the moon was every day of its existence. Suffice it to say that a few cm a year of receding from Earth isn't enough to fling the moon off towards Jupiter, at least not yet.