studiot

I see you are still on line so I will try to make this quick, but it may be a bit jumbled as a result. So carry on asking questions. You do not really need vectors or Newton's Laws to understand the Physics of this. The man in the trick is a single bodythat mey be considered as a single entity. He has no direct contact with the ground (or anything other than the truck). So pushing against the truck floor, as well as one side, is the same as pushing against the opposite wall of the truck or any other part of it. The is no overall or net effect on the ouside world. The fundamental physical principle is that internal forces always cancel or balance out. This is illustrated by the following. If you stand a book on a table the book exerts a force on the table due to its weight. If you stand another book on top of the first one then this book exerts a force on the first book which then transfers the extra weight to the table. Internal forces within the book cancel out. Can you draw a diagram to illustrate this ? It would help you to try first, then I will offer one. If you

I was going to say why do you not give us an example ? but re - reading I find you already did that but that your example is as obscure and impenetrable as the rest of your question. I agree that is sounds good in principle to ane the variables more meaningfully, but consider this: This was actually the way it was done years ago so Newton would have said, "Distance is proportional to time" (note they did not use equations in his day) This sounds better than s = ut doesn't it ? And further this is what is taught junior school. BUT What about s = ut + ft2/2 How about putting that into words ? Which would you rather learn ?

Yet another thought. I was thinking about the usual british house/garage layout with the garage either integral with the house (under a common roof) or adjacent to the house with a common wall. If the garage is actually a separated outbuilding then additional requirements apply, not least an extra isolation switch and the means of routing the supply cable The garage wiring cannot then be part of the house wiring directly. So it would be advisable to plan for the electrical work before the building work is done.

A further thought, he should consider adding an electric car charging point. That would add to the value of the property and he may be able to get a grant for it (about £500 I believe). That would definitely have to come off the main dist board as it is nearly equivalent to two ring mains by itself.

Now is the need for more information. Most properties have their meters/distribution box('fusebox') in or around the garage if they have one. It would certainly be better (and safer) if your friend could run new wiring from there. Is he proposing to get a board certification of alteration for this ? Sadly beaurocracy is steadily increasing these days, without any corresponding increase in safety

Sorry not directly no. You can have more than one spur off a ring main but only to one outlet (remember that can be a double) You cannot extend the spur to another socket. But there are some ways round this as in the hasty attachment.

How nice it is to have a pleasant converstaion with someone. Yes I am too old and lazy to learn LaTex or MathML properly so I use a commercial program called MathType. Here is a screenshot of me setting out a 3 x 3 array MathType give the option of copy/pasting in various versions of LaTex or other markup languages such as MathML. I use the MathML output on SF. Unfortunately MathML is quite expensive. So here are some sites which offer free online Tex you can copy/[paste from http://www.sciweavers.org/free-online-latex-equation-editor https://latex.codecogs.com/eqneditor/editor.php The only forum I have come across which offered direct LaTex in the editor was AllaboutCircuits dot com, when one of the administrators here at SF was administrator there. It was a bit 1990s clumsy but could be made to work. So come on @Dave and introduce it here. Final thing, Due to a glitch in SF software preview doesn't render Tex properly, you also have to refresh your page when viewing Tex initially. Hope this all helps.

Surely the basic Physics comprises the 'invariants' of the Theory ? In SR the invariant intervals form a network that requires no coordinate system whatsoever. In fact the addition of any coordinate system adds restrictions that are not present in the physics, in the similar way that the introduction of coordinate geometry restricts the geometry of Euclid. For GR the invariants are different and still being worked on to this day. https://en.wikipedia.org/wiki/Curvature_invariant_(general_relativity) https://link.springer.com/article/10.1007/BF02726036

Thank you +1 Still on your high horse I see. Building literature is full of examples of failures of tanking on the insides of basements due to external water pressure. I suppose I had better say that there are also other failure mechanisms as well in case you again think I mean all or nothing. Equally there are circumstances (not applicable to the OP) where internal tanking is the correct approach. For instance swimming pools, slurry tanks and other industrial fluid containers. The main point with the is that insufficient information was availble to pin down the reason for the tanking so I tried to offer an series of alternatives depending upon more information to be as helpful as possible to the OP and save a lot of questioning if he ever came back.

It's a pity you won't listen to others as your idea has the germ of truth in it. But not as you appear to expect. Strong and weak are relative terms so that neither of the above statements are absolutely true. But your idea that the force experienced by other charges varies with aspect for atoms (and molecules) is one of the most vitally important subjects in chemistry as it controls both chemical bonding and chemical reactions. Perhaps you should ask about this as the level of maths required is probably within your grasp.

But I was not wrong. That's the whole point.

It should be noted that a differential manifold does not mean the manifold is differentiable. It means that at least some functions defined on that manifold are differentiable. It does not mean that the coordinate system is differentiable - that has no meaning eg the statements x, y or the x - y plane are differentiable are meaningless by themselves. They are short form for functions lying in the x - y plane are (or are not) differentiable. The x - y plane itself is quite indifferent to whether some function is differentiable. A similar point can be made of continuity, but it is more complicated. Functions are 'continuous' or not as the case may be. Continuity for the space in which they lie has been broken down into lesser concepts of which connected is probably the nearest. Topologically a circle may be 'continuously' deformed into a wiggly loop. No metric or coordinate system is necessary for this. Topologically we talk of transformations rather than functions, although they are very similar.

Yes like I said, I gave you full credit for discussing ventilation. Are you suggesting I didn't ? You have yet to address my other point, responding you your vile and base attack on me, as you always seem to to.

Instead of being such a smartass why not find out the ideal or best way to do something, which may not be practicable and/or economic in some cases ? That was what was mean by my use of that small word 'should'. I gave you approprate acknowledgement for stating that sufficient ventilation may be the correct solution to the OP's problem, after all we do not know if the masonry actually is damp or not. So why can you not return the compliment ?

Perhaps if you paid as much attention to what I said as I did to what you presented you would not make such inappropriate answers. I did try to help you rather than just dismissing your stuff out of hand as others did. Clearly there is no point continuing.

Where did the OP state this room to be a cellar, I must have missed it. ? If you built a retaining wall, where would you put the waterproofing ?

This far from a foolish question and highlights a very important principle in mechanics. "A single body cannot move itself without interaction with an external force or other body" So to look at why you man in the waggon cannot push himself and the waggon, but the man ouside the waggon can. Simply put the man in the waggon has nothing to push against but the man outside pushes against the ground. There is a further twist to this you might like to think about. The man pushing the waggon can push a heavier weight (mass) than his own. Why is this ?

When discussing coordinates sytems and metrics is is important to realise that they are independent concepts. A space can have a metric but no coordinate system and vice versa. References to topological spaces have been made. Topological spaces do not require coordinate systems and some topological spaces do not require a metric. What is required for GR is continuity for the equations to make sense and the tensors to exist at all. Mathematics now separates continuity into several allied concepts ( coincidentally all beginning with C) and I did promise Joigus a thread on the subject. I suppose this is now becoming urgent.

I am aware of this since the neutrostatic field mainly rely on the bohr radius, this hypothesis (not theory) does not follow the equivalent principle when the bohr radius is significanly over or below the 5e-11meter distance. Therefore in plasma or in neutron state (I imagine neutrons have its electron very close to its proton), it couldn't hold up. A Neutron has no electron. So it is a particle with mass but no charge. So why does it respond to your proposed gravitational neutrostatic force ? The sphere is not a plum pudding model of an atom. It is a visualization of charge distribution on a conductive sphere. I understand that, so what is this ? I was actually referring to this diagram In both cases you have mixed up (arranged) the charges in an impossible way. Here is a clip of your dipole. A problem with this is that you have shown forces acting as though the positive and negative have equal masses. An electron and a proton have equal charge but very unequal masses. The mass of a proton is nearly 2000 times that of an electron. The mass of say a Uranium ion and an electron are tens of thousands of times different. If you mean by placing a conductor in the middle of the dipole, then the space permittivity will increase and reduce the neutrostatic field. Similarly if we can just simply reduce the bohr radius of the atom it would have the same effect. A neutron might fit the description. And for this, I will acknowledge that it is an obstacle with mainstream science. Yes I mean placing a conductive shield between the positive and negative poles of a dipole. But size has nothing to do with this. You could use the original device of Cavendish to do this. Charge one sphere positively and the other negatively and fit the shield between them. You would still find the same gravitational attraction as measured on the torsion balance. These are meant to be constructive criticisms of your proposal, not "I know more Physics than you so shut up little boy" type answers. You do not need advanced maths or physics to test your ideas and see that they are wrong because they contravene measurable reality.

I was reading through Mordred's long standing thread on space and I came across some posts from Mike in the early part. Members may wish to know that Mike passed away earlier this month after a long standing degenerative illness (not covid). Mike was an interesting character, an artist with a degree in Physics and the founder of a successful manufacturing business before retirement to Cornwall. His artistic (dreamy) side gave him an unusual and sometimes frustrating perspective on Physics, especially later in life when we knew him. But he was a genuine character and sometimes offered suprising insights as well.

Have you considered the possibility that your plumber may have had a point, even if his solution was less than ideal ? You mention that he thought your wall was damp. Was this ever measured ? You say that your wet room was being refurbished. If your previous wall covering (I note there is no plaster) was not perfectly waterproof, perhaps moisture was getting through from the inside and building up. If this was the case then the new wall finishes certainly need to be waterproof but the brickwork also need to be dried out first. Tanking (that is the correct building term) with bituminous or other waterproof membrane materials is the correct treatment. However the tanking should be applied on the same side of the wall as the source of the water as this will then mean that the pressure will hold the tanking harder to the wall. If it is applied on the other (wrong) side the pressure of the water coming through the brickwork will tend to blow the tanking off the wall. So if water is coming from the inside the tanking should be applied on the inside and if the water is coming from the outside then it should be applied to the outside. If you are facing internal tanking then there are special plasters/renders designed to adhere onto the tanking. You would need these in any case to tile or otherwise finish the walls. The bituminous tanking will loose 90% of its smell in about 1 week to 10 days. After this the appropriate render can be applied which will prevent the rest. Or you could simply remove the tanking (mechanically would probably work best) and do something else.

Can have a long life yes, if properly manufactured and installed. They said this about early transistors but then came the 'tin whisker' effect due to migration of metal from the leads into the semiconductor material and disabling the transistor. https://nepp.nasa.gov/whisker/anecdote/af114-transistor/index.html I said maunfactured and installed because this effect can also effect inappropriately chosen circuit board materials, solder, leads and other components as John has noted. We do not yet know if another unforseen effect will rear up and bite us in the ass in years to come. I have never seen a long life compact flourescent that achieved more than half the promoted service life bulb for instance.

I am going to say +1 for your efforts. Not only has this been one of the few speculations posted in accordance with the rules here (including the way you posted the video) but also it is a respectable train of thought that should not be lightly dismissed. However there are some points your hypothesis (not theory) has failed to address. 1)Neutrons have no charge whatsoever, yet are subject to gravitational effects. This is a serious obstacle. 2) Whilst I take you point about the generation of your field, you have taken situations that are electrostatic and combined them in a way that is forbidden by Earnshaw's theorem. Earnshaws theorem basically states the two or more charges in an isolated universe cannot ever be in equilibrium and therefore cannot ever be stationary or static. It is just not possible to have two charges and nothing else (ie no other forces) in the way you describe. Something else has to hold them in position if they are still. 3) The charge distribution you introduce on your sphere containing both positive and negative charges at about 3.5 minutes is incorrect. Thomson's 'plum pudding' model has long been (experimentally) discredited. 4) What would happen if I placed a long strip of continuous conductor between the positive and negative charges in your early diagrams ? The conductive material would fully shield each charge from the electric field of the other, yet there would still be a measurable gravitational effect between them.

To emphasise this, the degree of 'protection' depends upon the nature and quality of the grounding. Inadequate or wrongly placed grounding can lead to damage in its own right.

Hello Col and welcome. +1 for a good start, I look forward to further worthwhile contributions. I've been a member since 2012 and in that time I have seen many threads started discussing the question, "What is space ?" So it is indeed apressing question. So pressing that in fact we now need to separate what is meant by a physical space and what is meant by a mathematical space. Defining a mathematical space is easy. You need a set containing at least three (perhaps four) sets of objects. 1) A set of mathematical objects you wish to work with. 2) A set of coefficients you wish to apply 3) A set of axiomatic relations between these objects 4) Perhaps if you want to be complete then a set of results (theorems lemmas etc) you can deduce from these. Hi Markus, I think you have this the wrong way round. Mathenmatical structures are models of physical reality, rather than physical reality being a model of mathematics.