studiot

I thought you didn't understand it.

Yes of course he's right. The best way to think about it to to understand the word 'units'. A unit is 1 whole of anything. Even easier to think in terms of something that only comes in whole numbers for example eggs. So the unit is a single egg or 1egg. 5 eggs The 5 and the eggs are separate. So we have 5 x 1_egg. Similarly 5 metres is really 5 x 1_metre

I was working round to the vibration idea as I wondered if this KE reducer was suspended from the case by the diagonal lines in the diagram. And while yes momentum analysis is a good way of analysing the sytem I think the OP's problem is answering the questions The momentum of what ? The energy of what ? The KE is only the KE of the 'rocket' exhaust, not the system. The momentum is only the momentum of the rocket exhaust. But the rocket exhaust by itslef is a different system. It is so common for people to try to change systems in mid analysis and then wonder why things don't add up. It took long enough for the OP to admit that the system needed energy input (the electrical cables) or energy stored in another form eg chemical.

+1 +1

Our Math teacher worked on a weekly cycle. He didn't need, use a textbook except to set homework. I will start the cycle on a Friday. On Friday he picked up the textbook and looked at the set questions for the section/chapter he had been teaching that week. He picked out several questions saying do questions 3,5,6, and 9 or whatever. The other subject teachers knew to avoid weekends for homework. On Monday he would pick up the chalk, stand poised at the blackboard and say OK Smith, question 3 start me off. He would then write on the board whatever Smith said and the rest of the class were expected to comment if they disagreed. Once Smith had a correct start he would switch to Jones for the next step and so on until the answer was written on the board. In this way the whole class worked collectively through all the questions sometimes into Tuesday as well. He said, "I don't mark homework, you mark your own. At this stage you are old enough to realise the only person you can cheat is yourselves." On Tuesday/Wednesday he would walk up and down in front of the board expousing that week's theory and writing it on the board in his own way from memory. We would copy it down (enough time was given unlike at university). We could also stop him and ask for clarification or challenge a mistake at any point. He would always explain the point and not move on until it was clear. Thursday and Friday we would work collectively through example questions he dreamt up on the spot, in much the same way as the homework set on Friday. His comment on the textbook, "Now you are in the senior class you may be pleased to see that the (numerical) answers are in the back of the book. You may think that is great but will find it a introduces its own burden as you will not want to leave a question until you have got that answer."

What is not moving in the horizontal (x) direction in your coordinate system ?

Yes but it's more than just momentum. I think the poster has difficulty deciding what to include in the system, like many folks before him.

The wedge M is moving sideways to the right only. It has zero vertical movement. mass m is moving downwards and to the horizonally to left relative to the floor, but at the same time it is sitting on wedge M so is also moving to the right the same as wedge M. So mass m has a net sideways movement relative to the floor of two motions. Does this help? Hint think about what swansont said about coordinate systems.

+1 We are all working towards showing that with proper analysis the proposed system can be analysed conventionally, as expected once all the details are teased out.

How can I consider curvature flat ? What does this mean? I asked because I am questioning the quote from Quora and your understanding/use of it.

This comment might help you look further.

No problem about the clarity I understood the question well enough and that's what discussion in Homework help is for. Yes you are correct that the wedge M slides along the table or floor in the horizontally opposite direction to the mass m. It is important to understand that this happens while the mass m is sliding down the slope. So the motion of the wedge M is simple, but the motion of mass m is complicated because it's total acceleration is the resultant of three accelerations. Can you see what these are ?

Thank you for this information. +1 Obviously my scribe was having a bad hair day since so many misunderstood his scribblings. I didn't say my link supports or does not support any particular source of water vapour. I said it states that water vapour is the biggest single contributor. It doesn't matter how the water got there it all adds up. So consider the skies over a desert termite. How much water vapour is present ? All this discussion is proving is that atmouspheric dynamics is complicated and multifactorial. In the carboniferous period carbon dioxide levels were high as were temperatures. But then so were oxygen levels. Do you consider oxygen a greenhouse gas ? We couldn't have either water or carbon dioxide without it.

So you are using some of that electrical input to stuff the genie back in the bottle, sorry drive the compressor, also inside the box to repressurise the gas cylinder ? The question was not answered, just neatly side stepped. What else are you not telling us ?

So why did you respond by linking to a paper that states explicitly methane is oxidised? I have quoted this once directly from your post but here it is again for your convenience I still think you misunderstood my post and still do. But I am with you on a good deal of your thoughts here.

Seems to me that Your diagram does not show the small block at the top of the wedge , as stated in your words. Why not ? You have not mentioned friction anywhere or conversely smooth contacts. Are we ignoring friction ? What do you understand as the significance of the ratio M/m = k ? Can you describe in words what movements you think could take place ? You should have done this last step before starting force analyses.

Indeed so. That is how a released balloon flies away if the neck is open. But so what, perhaps your rocket is a cylinder of compressed gas. The question still arises how long will the exhaust last ? This proposal of yours reminds me of Edward De Bono's 5 day course in thinking. In his first lecture he has a 1 foot cubical box sitting quietly on a table in front of him, roughly in the middle. About halfway through there is a quiet bang and the box falls over onto its side. The lecturer ignores this, but at the end sets a task to explain how the box fell over by itself during the next four days.

I blame Apple myself (Along with the second deadly sin)

Thank you for your clarifications. On to my next questions. I understand you are firing a rocket engine inside the box. Since no air is allowed to enter what are you using for oxidant ? How much of the 14.6 kilos is fuel and oxidant and how long will that last in time ?

Thanks for the support of my comments. I apologise for the poor spelling in my post. May I respectfully suggest that renovation of governments would be a far better option ? You misunderstand. Oxidation of one molecule of methane (CH4) produces one molecule of carbon dioxide and 4 molecules of water. You misread that somewhere bro. The international CO2 equivalent for methane is 25. However water vapour is the biggest contributor to global warming so producing 4 molecules is bad news. https://www.acs.org/content/acs/en/climatescience/climatesciencenarratives/its-water-vapor-not-the-co2.html

I was watching a BBC regualr programme This evening - Countryfile. This week they were visiting England's (and also one of Europe's) largest artificial forest - Kielder Forest. They had some interesting facts to offer. The forest was first planted in 1920 to make the UK independent of foreign timber sources, following the experience of the 1914 - 18 war. Timber currntly being harvested was planted in the 1950s. For every acre harvested they replant 2 acres. The recognise that, young or mature, most of their trees are unsuitable for biodiversity so they employ a specialist team to create alternatives within the forest, for instance nesting boxes for owls that normally nest in natural holes in trees, platforms for Ospreys (naturally returning after 250 years absence) insect, fungi etc being also catered for. Apparantly Kielder supplier 25% of the UK building timber. And they point out that building timber in fixes the carbon content for hundreds of years in roofing, flooring, etc. And then, termite activity is not restricted to old-growth forest; much of it is directly related to human habits and habitats. Surely oxidation of methane meand creating carbon dioxide instead ? Wherever the termites are located how is this better ?

I am not interested in how this 'KE converter' is alleged to work, although I can think of a number of possibilities. I am, however interested in a discussion which involves the correct statement and used of the terminology and laws of both Mechanics and Thermodynamics. Let us start wiht the use of the term 'closed system' Your system is not closed . Energy of one sort or another can pass the system boundary to and from its environment. Closure of a system simply debars the exchange of matter (ie mass) between the system and its environment. If the system were isolated then energy would also be debarred. Having corrected your terminology we come to your statement of the law of conservation of energy. (Top right in your diagram) Before considering this I would appreciate a little more information about your system boundary. From your earlier description I am given to understand that the black rectangular boundary in your diagram represents something like a shoe box or packing crate that will spontaneously move sideways when you press the go button. This behaviour would occur where it is currently located in your back yard, garage or whatever. But would also occur if you picked up the box, drove 1,000 miles into the desert with it and set it on the ground before pressing the go button. Is this a correct description ?

Two things about this. 1) Marine carboniferous rocks are not the only ones formed. Peat, lignite, coal ,oil to name but a few. 2) One beneficiial effect of temporary storage of carbon as vegetation material is much the same as the argument against hard paving over evry one's front gardens. That accelerates the run off which exaggerates the peaks and floods.

You posted both statements here, just as I used the quote function to place them together in my question. Where you obtained those words is not relevent, exccept you should attribute them if they are someone else's words and be prepared to back them up. I even rephrased that question to ask That asks where the exterior of the Higgs field is if the H field fills all space Since the universe, by definition, comprises all there is, where is this 'exterior' ? You answer does not satisfy this property of the universe as being universal. You are still ignoring my question of what binds uncharged nucleons to other nucleons if the strong force is electromagnetic ? I also asked you what you thought a Field to be and, in fairness, you did reply. But your definition was far to narrow, involving only energy for isntance. Here is my working definition. I don't claim that it is complete. A connected region of any space, whether a real physical space or an artificial theoretical space such as phase space, is said to contain a field of a quantity of interest if a value for that quantity can be assigned to every point in that region. That defines a Field in the way that Physicists use it. A Field in Mathematics is quite a different thing, so be careful which sort you mean. So to specify a field, you need to specify three things. The region, the quantity, the boundary conditions if any, since some Fields have no boundary. Relationships in the form of equations are also useful in analysing the properties of that Field. The last statement about relationships is vitally important because the field of a single isolated source eg gravitational or electrostatic or magnetic, contains no energy. I am fond of the expression "It takes two to tango", which expresses the fact that you need at least a second object to introduce 'energy'.

No problem. I agree that is likely the case. But you don't need to quote me or anyone else to post your thoughts in a thread here. Just post stuff which makes sense like this and you will do well.