John Cuthber

Yes you are, you just haven't realised it yet. Imagine you build the wheel, and it works You manage to raise the water to the top of the slide using less than 50 KW- say it takes 25. That's nice for you. Now imagine I build a similar wheel alongside. But I don't use it to feed a water slide- I use it to drive a turbine and I use that turbine to drive a generator. I know that I can extract nearly 50 KW of power from that turbine (because the maths is exactly the same as before). So I can use 25KW of that power to run the wheel and I have 25KW left over to sell. I'd be getting power for nothing. But we know that is impossible. So we know that the wheel can't lift the water using less power than the turbine could generate. So we know that the wheel can't take less than 50KW of power to raise the water.

His behaviour on that count suggests that he doesn't really understand what he's on about; and he knows it. I guess the book he is parroting doesn't answer those questions for him.

If truth isn't real then you cannot establish the truth about anything- including truth. So, if we plan to get anywhere we had better assume that there are at least some objective truths- for example, we are people living on a big rock. I'm not saying that statement is correct, I'm saying that if we assume it isn't we get nowhere. Science treats the existence of objective reality as an axiom.

He introduced quite a lot of twaddle, notably this. "Incidentally, the physics that explain the lift of an airplane are the same as the physics that explain the lift of a helium balloon."

Indeed, and it still as nothing to do with the topic.

The balloon won't fly in a vacuum. nor will a plane. Another thing that won't fly is the idea that flight in a vacuum is the context of this thread. The source of energy is indeed external to the balloon. But if you had a balloon twice as big you would have twice as much energy available for the generator. Ignoring the fact that the balloons would burst, if you tied two balloons together by a string and hung them over a pulley nothing much would happen. But if one balloon was full of air and the other of helium, the helium balloon would rise. So, in that context, a helium balloon would rise in a vacuum.

Whether a rock has gravitational potential energy or not depends on where your baseline is, and you can't say for certain whether its energy is positive or negative. However when a helium balloon rises it does work against the viscosity of the air and heat is produced via friction. The ability of a balloon to fly i.e. lift a load relies on it having stored energy. Once it has lifted the load it has less energy. In context it's perfectly clear that the potential energy of a helium balloon is lower when it's high up. Perhaps the most important point here is that it has nothing whatsoever to do with the topic. Why air planes fly isn't really the same as why ballons fly

OK, Lets try that again, but do it properly. If you want to calculate the gravitataional potenetial energy of something it's easy enouh E= m g H where m is the mass, g is the local gravitational acceleration and h is the height above some datum. There's a similar calculation for weight w = m g So you can rewrite the first equation in terms of weight the gravitational potential energy is given by E = w h where w is the weight and h is the height. But, for a helium balloon, measured in air, the weight is negative. So the more height you have the more negative the energy is. The problem is not that I had forgotten that helium had mass,but that you had forgotten that its weight is negative (if measured in air at a comparable t and p). Blindly quoting high school physics doesn't get you very far in this case; you actually need to think about the system and the forces involved. So, as you have been asked repeatedly, and as the rules require, Perhaps you might like to tell us where the energy to run the generator comes from.

What I'm thinking is the same as what I'm saying.. If the balloon can give energy to something else as it rises then it must lose energy as it rises. So it must have less energy when it it high up. Would you like to explain where else the energy might come from?

You did get an answer. You have got the same answer repeatedly. It takes at least 49KW

These people told you it's 49KW https://www.physicsforums.com/threads/making-ancient-time-water-wheel-to-lift-water.784503/ So did these http://www.thescienceforum.com/physics/47711-possible-make-energy-efficient-ancient-time-water-wheel-lift-water.html And (roughly speaking) these http://www.thenakedscientists.com/forum/index.php?topic=52915.msg444395#msg444395 so why are you asking again?

There should have been a discussion before any work started to sort out what the risks were and what could be done about them For example, I'm sure there's a vaccine against whooping cough. Wouldn't it have been a lot better to get that jab first?

At best, it might be marginally more efficient than a more conventional pump. My guess is that it would be less efficient.

Well, I'm guessing that's what he meant. It hardly matters- an unclear logical fallacy isn't an improvement on a clear one. If I wanted an expensive taxi driver the ppl would be relevant (Though I'd probably ask a mate of mine who teaches people to fly helicopters).

For a start, there's no way that could possibly be your decision is there? You don't get to decide what we want; so you are just being silly when you say " I've decided that none of you want to learn" The idea that I don't want to learn does not make sense and you know it. If I did not want to learn,, I would not keep asking questions. So, here we go again. How do you explain this? "Also, you have not explained how a balloon on a string can generate electricity by rising unless that energy is taken from the potential energy of the balloon. If energy is taken from it as it rises then it must have less potential energy when it's high up." on the other hand, if you wanted to learn you would try to answer the question. it is you who refuses to even try to learn, not us. Having a private pilot's license has little to do with knowing how a plane flies.* Plenty of people drive cars without having the least understanding of the mechanics of the engine. Why did you mention it? Did you think it would impress us? Boy oh boy! you have e lot to learn. * The proof of that assertion is that you have one, but don't know how a plane flies.

You have had years of notice- why haven't you done something about it? Also, if you are a big enough organisation to be paying £10,000 in fees then you must be a pretty big organisation. can't you afford it? http://www.cirs-reach.com/reach/REACH_Registration_Fees.html Incidentally, the 64 Euro fee probably doesn't even cover it's own processing costs. So I'm not sure what you are on about. Could you explain a bit?

Yes, don't care, don't care and No respectively. Now can you please do hat the site rules require of you, and answer my question about the generator?

Does the book answer the questions we have asked? Does it, for example, explain this "Also, you have not explained how a balloon on a string can generate electricity by rising unless that energy is taken from the potential energy of the balloon. If energy is taken from it as it rises then it must have less potential energy when it's high up." Does it explain why your bizarre ideas about why balloons shouldn't float because there are compressed air tanks on Earth tally with reality? If not, why would I buy it?

Why do you ask? This site says it's about twice that http://hyperphysics.phy-astr.gsu.edu/hbase/astro/astref.html but it's not an easy thing to estimate.

It is unfortunate that many countries are not able to fund their own research, nor even to benefit from the research of others because the subscription costs of journals are high. What would be even more of a tragedy would be if those limited funds were spent on journals that are utter rubbish. Even if it is free, a bad journal is, at best, a waste of time. It may also be misleading.

It's also not clear to me that, with a population of about 7 billion and rising, on a finite planet, we need to find more ways to reproduce.

3 and 4 contradict each other. Newly emerging fields need new journals otherwise the scope of the established ones gets overgrown. However, a new journal logically can't have already got articles published by recognised experts. There are, as you say, ways round this issue. One is the launch of a spin off journal from an established one.

The Moon is roughly a sphere. Any plane is parallel to two points on the Moon's surface. The reflectors were placed so they faced the Earth., that means they were pretty much parallel to the Moon's surface at the point of the Moon nearest to the Earth. Of course, in practice, the reflectors were not plane mirrors, but corner cube arrays. Who cares? You can bounce a radar signal off the Moon, without needing to put a mirror on it.

Not wimpy, or even corruptible. Lazy would do. As far as the soldier is concerned the guy is dying or dead. Why waste your effort sticking a spear in him? Ok, he could get into trouble for not following orders, but who is going to report him? . Christ? His followers? Nobody else is going to look at the corpse- seen one , seen them all. Besides which, according to the account, he did stab him. I just wonder how deeply

Easy, we can check it in the ;lab. OK you would need a rather large lab to do the experiment on the million year scale, but it's easy these days to measure propagation delays as we bounce em signals round satellites or reflect light from the Moon.