studiot

If this were a science story then would we not approach it more rigourously? 1) Theoretical perpetual motion is required, not forbidden by the laws of mechanics. 2) The laws of Thermodynamics proscibe two types of perpetual motion machines or processes. The first proscription concerns the first law and I would hazard a guess that the problem here is the age old error of improperly defining the system boundary, leading to inappropriate conclusions. The second proscription concerns only cyclic processes or machines. This proscription does not apply to parts of a cycle. If I could obtain a proper description of what the OP is proposing I could comment further but I fail to see either a definite system boundary or a cyclic machine or process described in the material presented.

Here is an a video of a glass of liquid during an airplane roll. https://www.youtube.com/watch?feature=player_detailpage&v=uw2qPLEgKdQ#t=3

I wondered about that, I didn't think of a bicycle, though I've just pumped up a tyre this afternnoon. +1 I haven't the resources to do any graphics until June. BTW I also never knew St James berries were red

Thanks for the video, Google didn't find it for me.

We have had umpteen threads about forces and accelerations on rotating bodies, without result, so here is a question for those who think they know. Put a cup, half full of tea, on the outer edge of a motorised lazy susan and spin. What will happen to the surface of the tea in the cup. Will it rise up one side, if so up the inner (close to the centre) or the outer? What does this mean for the centrifugal v centripetal argument? I have tried to find a video of this experiment without success. I can only find videos showing the vortex created by spinning the cup about its own axis. So I woudl be grateful if anyone can offer one.

In fairness to overtone, I have observed the application of the 'rules of the scientific method' to be subjectively applied generally (including on this forum) in support of a particular person's view. That is, unfortunately human nature. It is really difficult to be truly objective. Here is a good summary discussion of the scientific method, including the difference between deductive and inductive routes. There are also good sections on the limitations of the method, types of evidence and fallacies. http://www.scientificpsychic.com/workbook/scientific-method.htm

The 2012 James Mackenzie lecture at the Royal College of General Practitioners by the late Professor Helen Lester has much of worth to add to the OP story. Actual facts, figures and most of all, compassion. The first few minutes of the lecture https://www.youtube.com/watch?v=tqyACm5OQOM

I have ignored other minor errors as typos anyone could make, and I make all too often. However for someone to preach to me about the English language and any connection it might have to Mathematics should start by getting his facts right, not wrong and then repeating that error. What is an explanation mark? The problem about discussing or not discussing your ideas as I see it is that, whilst on the one hand you are inviting comment, on the other you are making contradictory statements about any comment and being quite rude about it. ajb, in particular, has offered you some mathematical insight taking mathematics beyond the simple definitions that could be entirely applicable if your ideas were serious. That you reject them out of hand suggests to me you are not, but simply trolling.

'Straight' is a modern translation of what Newton actually said "In its right line" Which will actually satisfy the requirements of geodesics on in a manifold, which simple 'straight' would not. A straight line in 3D is described by the intesection of two planes and therefore satisfies the equations of both of them simultaneously. There is not one single equation to describe a straight line in 3D (euclidian space), but a pair of simultaneous equations.

And what does truly straight mean?

Immediately behind the gun of course, since it is well known that immediately in front of the gun is the safest place on the firing range.

With election fever upon us here is an interesting proposed derivation of the word Parliament. Scroll down to the end of the article. http://www.bbc.co.uk/news/magazine-32273170

This belongs in homework. I will make a small adjustment to DrP's post Integration by parts is for a product of two functions u(x) and v(x) but not directly multiplied, since one is a differential. [math]\int udv = uv - \int vdu[/math] You need to chose the u as the function that can most easily be differentiated and the dv as the function that can most easily be integrated. (sometimes there is little to chose between) So in this case chose u = x and dv = sin2x Can you take it from here, you should have three terms in your answer

Is this coursework? In which case it belongs in homework help. What happens if you take the log of both sides of your equation and then differentiate each side?

I would starty by explaining my question in a bit more detail. What you said may be OK in a classroom when you are in the middle of discussing the subject and have lots of context, but i am not sure what you are asking. Are you talking about steady running and load on the machine or accelerating a load from a standing start? Both the power and efficiency are affected by the compression available in the cylinder, if the slider is a piston. The speed of running and the mass of the piston will also be involved. Or are you just asking how to maximise efficiency - ie reduce friction etc?

I don't know what the flow rates are for a hyperbaric chamber.

Well my calculator made it 16.3 mins - say 15 mins for safety. A 5L tank at 50 bar expands to 5x50 = 250 L at 1 bar. Leave 5L in the tank as spyman said makes 245L available. Using this at 15L/min is 245/15 = 16.333 mins.

For the benefit of the OP and others, instead of squabbling further with john cuthber, here is a physics 102 exam paper extract, with answers. This shows, amongst other things, a wave that is both amplitude and frequency modulated. http://www.physics.umd.edu/courses/Phys102/brill/EX2-2.HTM

Sorry, I wouldn't know I've never been on a social media site, I not sure i would even know how. However you are correct in that this is based on something I read in our local what's-on rag, 'Suited and Booted', with my own take on some of the items and some additions of my own. However the subject has clearly put put up for wide discussion in the public domain, which is what we are doing.

Please stop all this holier than thou stuff and look at the pics, courtesy g3npf. The top one is AM the bottom one is FM If you look carefully you can see visually what I am saying. The frequency of the AM carrier is fixed and does not vary. The frequency of the FM carrier varies continuously from (fc-fd) to (fc+fd). Every cycle of the FM carrier has a different period. End of.

Go at it folks. It depends on your definition of 'green'.

Are you asking because you actually want to find out the correct answer. Since you clearly misunderstand frequency modulation I will try once more. In frequency modulation the carrier frequency is varied in accordance with the amplitude of the modulating wave. The maximum is known as the deviation frequency fd

Checking out at the supermarket recently the young cashier suggested I should bring my own bags because plastic bags were not good for the environment. I apologised and explained, “We didn’t have these things back in my earlier days.” The cashier responded “That’s our problem today. Your generation did not care enough to save our environment for future generations.” Back then we returned milk pop and beer bottles to be washed, sterilised and refilled. We walked to the local shops and didn’t climb into a car every time we had to go two minutes up the road. Back then we washed babies’ nappies because we didn’t have the throwaway kind. We dried them on a clothes line, not an energy gobbling machine so wind and solar power really did dry our clothes. Kids got hand-me-down clothes from relatives, not always new designer labelled stuff. Back then we had one TV or radio in the house, not one in every room. In the kitchen we stirred and blended by hand rather than having electric machines for everything. When we posted a fragile item we used screwed up old newspaper as packaging, not plastic foam or bubblewrap. Back then we didn’t burn petrol to cut the lawn. We used a push mower that ran on human power. We exercised by walking and working so we didn’t need to go to a health club to run on exercise machine run by electricity. We drank from a fountain instead of purchasing plastic bottles of water. We refilled ink in writing pens and replaced blades in razors. Back then we took the bus and kids rode their bikes or walked to school. A stag night meant a few mates going on a pub crawl, not two dozen people flying to Prague. Back then we didn’t need a computer to receive a signal beamed from a satellite 2,000 miles out in space just to show a photo of a meal we had just prepared to a friend who lives next door. But, of course we weren’t green back then.

No not really, but your are claiming they are the same so why do we have two terms? While you are at it perhaps you would like to resolve the following. In an AM signal the carrier frequency does not alter. It is constant. In an FM signal the carrier frequency is constantly varying. The deviation from the carrier centre frequency is proportional to the modulating signal amplitude. In an AM signal there is no modulation information in the carrier. In fact it is possible to remove the carrier entirely and some forms of AM do exactly this. In an FM signal all the modulation information is contained in the carier. Removal of the carrier will result in total loss of the information. A clear difference there.

I didn't say anything of the sort. The broadcast signal has an instantaneously unique frequency and amplitude. It is one signal. It is not several signals. The best way I can explain this is to consider a cyclist. At some particular instant he is cycling North East at 14 mph. Now mathematically we can resolve his velocity into 10 mph North and 10 mph East. But there is still only one cyclist, not two travelling on two different directions. At another instant he may be travelling at a different velocity with differents components in the north and east directions. In the same way the broadcast signal is one signal that may be mathematically resolved into components, not in space but in time or frequency. There are more and different and resolutions possible for these generalised coordinates.