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    Physics General Subjects Thread

    kvs
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    Post  kvs Wed May 12, 2021 2:54 pm

    https://www.zerohedge.com/energy/nuclear-reactions-chernobyl-cause-concern

    Nuclear Reactions At Chernobyl "Cause For Concern"

    Imbeciles.

    There is nothing left at Chernobyl that matters. The residual corium is not in the process of concentrating and even
    if water is transporting some of it to pool and desiccate, that is never going to produce another meltdown and
    will just enhance the neutron flux for a short time.

    This is from a country that is at extreme risk of having real nuclear meltdowns at this remaining power plants on
    account of corruption and negligence. Still milking Chernobyl for propaganda value. Poor, poor Ukraine.

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    kvs
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    Post  kvs Thu Jun 03, 2021 2:45 am



    The million dollar question is why a black hole did not form at the galactic center if this new proposal is true. If there is a drag on stars
    and other objects through this compact dark matter halo, then over time there would be coalescence of these objects on the center of
    mass. Without such a drag, they could keep bouncing around in non-colliding orbits for billions of years. But even without a drag,
    this neighbourhood is way too busy for no large body formation over long periods of time through close approach mass siphoning. The
    various objects doing their orbital dance are not point masses or even exclusively condensed matter. Over time a large predator star
    could grow big enough to form a black hole.

    Or maybe black holes are BS. And every object claimed to be one is actually a compact massive object that is not a star with the
    fusion of hydrogen. Maybe dark matter is not a magical substance that never gets dense enough to form compact objects. The existing
    theories are weak and there is way too much circular thinking where the theory is used to interpret the observations and not the other
    way around.

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    Post  kvs Fri Jun 04, 2021 7:21 am



    kvs
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    Post  kvs Thu Jul 01, 2021 7:44 pm



    Another excellent video in the series of celebrity physicists who have the strong stench of shysters.

    Note the observation about the onset of arrogant physics after WWII via America. America and snake oil salesmen
    are inseparable. Elon Musk is a sample of such snake oil peddlers who are famous supposedly for being great innovators.
    American exceptionalism is a plague on the world.

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    Post  kvs Fri Jul 02, 2021 3:56 pm



    Cocky pilots think that they can fly near the ground with no risk of crashing. They need to buy a clue and get educated. This
    plane was 20 minutes from landing so it was already descending and below 5 km. It dropped nearly 1 km in a few seconds and
    people inside were in free fall like on the "vomit comet". This is not "turbulence". This is an organized feature of the circulation.
    The clown who crashed the first SSJ-100 into a volcanic ridge assumed that his aircraft would always have the lift needed and
    all he had to do was use his skillz. Well, life ain't so simple and smarmy show-offing makes you a candidate for the Darwin Award
    which unfortunately also translates into "death thanks to an idiot" awards for others.

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    Post  nomadski Sun Jul 11, 2021 1:19 pm

    Question from Electrical engineers of physicists regarding cheap power generation. Because of lack of revenue due to falling oil sales, the government in Iran did not invest in power generation for the last 10 years. Because of this and lack of rainfall and low levels in Dams, Hydro-electric power generation is also low. Shortages are causing damages to economy and increasing social tensions.

    Because of this, I ask a question from experts about the cheapest and most direct way of electric power generation for villages and small towns. By cheap, I mean initial capital expenditure and not running costs. And I am not concerned immediately with pollution effects. What do you think can be done to provide electricity for villages that allow power to be diverted to industry?

    My own idea is to use a series of vehicle diesel or petrol engines in a series, each coupled to a generator. Iran produces car Engines of various types. So capital expenditure should not be high for government to purchase them. I am not sure about generators. Does Russia or China produce small electrical generators that they can provide ASAP to Iran? Are there any other power generation that can be used immediately?

    https://www.wartsila.com/energy/learn-more/technical-comparisons/combustion-engine-for-power-generation-introduction

    Supposing a bank of 10, 50 HP car Engines coupled to generators, how much power in kW, can it produce? How many fridges can it run or light bulbs ?

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    Post  kvs Sun Jul 11, 2021 3:10 pm

    Diesel generators are the cheapest for villages. Small towns can be covered but not really large towns and small cities. Gas powered
    generating stations like the ones built in Crimea are what you need. Iran has huge natural gas reserves. I am not sure about pipeline
    infrastructure, but for a country as big as Iran, both pipelines and power stations are affordable. Of course, it takes time to build
    this infrastructure and short term needs at the village level can be handled by diesel generators.

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    Post  nomadski Mon Jul 12, 2021 6:41 am


    Yes it seems the best short term solution, before more Nuclear power plants are built. Iran's needs right now about 20 Megawatt to avert problems. This is around 1000 medium size generators. I think Iran manufactures own diesel marine Engines. So they could make savings there. Can Russian company provide 1000 generators? Or provide complete units on lend / lease basis? Or even Russian military provide some emergency mobile generators?

    https://www.tss.ru/eng_about/

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    Post  GarryB Mon Jul 12, 2021 11:27 am

    Dare I say it... you would be impressed about the savings in power just switching to low energy lighting... even just for streetlights...

    It would be useful to find out what most domestic electricity is being used for... heating, cooling, lighting, running various appliances etc etc.

    In remote places if you do all your cooking and heating with gas or just fire and electricity is mainly for lighting then a couple of old car batteries and a electronic battery regulator and a solar panel and wind generator and you are good to go.

    I have seen a light bulb used in Africa that is rock powered... you attach a rock and it pulls down on a string which is used to power the light... ie gravity powered.

    Heating is by far the most common way electricity is used because heating is generally electricity intensive, so alternative forms of heating should be looked at like fire or gas.

    I think Iran manufactures own diesel marine Engines. So they could make savings there. Can Russian company provide 1000 generators?

    Make sure you have the fuel to run them before buying.

    Energy saving light bulbs and other energy saving ideas can be explored too.

    Gas turbines are also used for electricity generation... when run at efficient speeds they can be useful for generating electricity of a wider range of fuel types and if you set it up properly it could be used for heating large buildings at the same time...

    Ironically when the rains do come they will probably come all at once so flooding will be is issue too... mother nature is a btch.
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    Post  kvs Mon Jul 12, 2021 3:44 pm

    nomadski wrote:
    Yes it seems the best short term solution, before more Nuclear power plants are built. Iran's needs right now about 20 Megawatt to avert problems. This is around 1000 medium size generators. I think Iran manufactures own diesel marine Engines. So they could make savings there. Can Russian company provide 1000 generators?  Or provide complete units on lend / lease basis? Or even Russian military provide some emergency  mobile generators?

    https://www.tss.ru/eng_about/


    For large size diesel generators that is a big one-time order. Production volumes for engines for cars and trucks are much larger, but these are
    larger diesel engines and associated generator and electrical components. So the volume is smaller. It is possible to buy from China, Russia and
    probably India as well. This way there is no demand shock.

    I agree with Garry's observation, it is possible to do some belt tightening and find 20 MW in a country the size of Iran. But if the villages don't
    have access to the national grid, then some cost and time will have to be invested.

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    Post  limb Mon Jul 12, 2021 8:10 pm

    Can anyone explain to me if the tesla cybertruck's aerodynamics are any good. According to common sense, theres a reason all cars have curve, but the cybertruck is very blocky and edgy.

    All the articles touching upon the drag claim its actually very good but that seems a bit fishy
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    Post  kvs Mon Jul 12, 2021 8:40 pm

    limb wrote:Can anyone explain to me if the tesla cybertruck's aerodynamics are any good. According to common sense, theres a reason all cars have curve, but the cybertruck is very blocky and edgy.

    All the articles touching upon the drag claim its actually very good but that seems a bit fishy

    Compared to the existing pickup trucks it is definitely of lower drag. The nose cross sectional area is not
    larger and is sitting lower to the ground and the windshield is sloped in low angle from the leading edge.
    The rear of the cab is also sloped instead of being at 90 degrees. So streamlines do not form a perpetual
    vortex at the rear of the cap and in instead flow to the rear tail gate where both the cyber truck and
    regular pickups have a standing vortex. These trapped vortices act to sap kinetic energy from the vehicle.

    I have not seen the numbers, but the cyber truck should be substantially less drag than existing pickups.
    At one stage Dodge was going in the right direction (early 1990s) but then reverted to the standard blocky
    shape because the dicks who buy such vehicles think that aerodynamics is for faggots.

    There is a limit on how aerodynamic the cyber truck can be. It still has a large gap between the ground
    and the chassis. Note how sports cars practically hug the ground. This reduces drag substantially since
    the streamlines then flow over the top instead of dragging over the rough bottom of the vehicle. For
    sports cars this acts to keep them planted firmer to the ground. The nose of the cyber truck is still a
    flat "paddle" pushing the air instead of diverting it over the top. Pickup trucks and trucks will always be
    less aerodynamic than the sedans and sports cars. If Musk is claiming otherwise, then he is just pushing
    his usual snake oil.

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    Post  GarryB Tue Jul 13, 2021 9:02 am

    Fishy would be hydrodynamics, same thing but with a denser medium... Twisted Evil
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    Post  nomadski Wed Jul 14, 2021 10:46 am

    @Garryb

    "......Gas turbines are also used for electricity generation... when run at efficient speeds they can be useful for generating electricity of a wider range of fuel types and if you set it up properly it could be used for heating large buildings at the same time...

    Ironically when the rains do come they will probably come all at once so flooding will be is issue too... mother nature is a btch......"

    It looks like they have decided to build mega- generators for industry. I think this plan as well as being more expensive, is also more vulnerable to attack, compared to small dispersed diesel generators. More resistant to air attack. Also I remember during Dr. Ahmadinejad, Iran used underground cave systems to store fuel. Or there was a plan. They could do the same with water. Store underground, instead of lake or reserviour or Dam. Since again can be hit, like Iraq and Afghanistan. Or water poisoned. Store water for a rainy day! Build underground Aquifers. Use existing empty military tunnels for water storage.
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    Post  kvs Mon Aug 09, 2021 4:05 pm



    Next time someone goes on about 3 nm IC resolution, then you can link this video how "3 nm" is really just a marketing number
    which means diddley squat. This post is a continuation of the one upthread showing that real component sizes in "7 nm" FinFet
    are 10 nm. All the yapping about going down to 5 nm or even 3 nm is full on rubbish. At 3 nm the thermodynamics of the
    semiconductor material no longer apply as we begin the transition to molecular clusters. The parasitic current leakage at 3 nm
    cannot be controlled and is terminal. That is physics and you cannot wish into existence material properties you are leaving
    behind.
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    Post  kvs Fri Dec 03, 2021 1:13 am



    lancelot
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    Post  lancelot Fri Dec 03, 2021 6:11 am

    I enjoy watching Thunderf00t's videos but in this one like quite often he uses some misdirection in parts of the video.
    He is correct to lambast the Youtube channels pushing this drivel message out and making all sorts of erroneous statements.

    But metal hydride hydrogen storage is a real technology which has been worked on for decades. He is correct that the main issue with it has always been that it weighs a lot more than just storing the hydrogen because of the matrix you use to store the hydrogen gas into. But the whole point of the matrix is to be a more compact way to store the hydrogen volumetrically. He himself points out how CH4 is more dense as an hydrogen storage method than H2 because of the molecular configuration of it. The matrix is a cage to force the hydrogen molecules to be stored more compactly than they would otherwise. Hydrides enable more compact storage, and no it is not on the level of compressed hydrogen in terms of volumetric density, it can be better and often is. Hydrides also have the advantage they are a lot safer as a hydrogen storage medium than other alternatives in terms of shock resistance for example. He is also correct that it usually requires a lot of heating energy to release the hydrogen gas from the hydride and that has always been a stumbling block. So the conclusion is this technology is likely a long way from being marketable, if ever, I personally think hydrogen cars are a complete non starter given electric cars have much more superior characteristics. You waste a lot less energy with electrics. Even if for whatever reason you want to eliminate gasoline, it makes a lot more sense to just use CH4 directly. It is readily available and is a lot more dense than hydrogen.

    One example of what the people in the Youtube channels he's quoting get wrong is the quotes the company which develops this product make about using sewage and other "greenhouse" waste gases as an hydrogen source. He claims CO2 has no hydrogen in it. Well duh. The company isn't talking about CO2. They are talking about METHANE GAS (CH4) which you can get from sewage and landfills. But like I said, I would just burn it directly. But for whatever reason people seem to believe the AGW agenda and that's the excuse companies like these use to push things like hydrogen storage on us.
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    Post  kvs Tue Dec 07, 2021 3:42 pm



    Another video exposing and debunking US "high tech" "raspil" (Russian for fraudulent extraction of money).

    kvs
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    Post  kvs Tue Dec 07, 2021 3:50 pm

    lancelot wrote:I enjoy watching Thunderf00t's videos but in this one like quite often he uses some misdirection in parts of the video.
    He is correct to lambast the Youtube channels pushing this drivel message out and making all sorts of erroneous statements.

    But metal hydride hydrogen storage is a real technology which has been worked on for decades. He is correct that the main issue with it has always been that it weighs a lot more than just storing the hydrogen because of the matrix you use to store the hydrogen gas into. But the whole point of the matrix is to be a more compact way to store the hydrogen volumetrically. He himself points out how CH4 is more dense as an hydrogen storage method than H2 because of the molecular configuration of it. The matrix is a cage to force the hydrogen molecules to be stored more compactly than they would otherwise. Hydrides enable more compact storage, and no it is not on the level of compressed hydrogen in terms of volumetric density, it can be better and often is. Hydrides also have the advantage they are a lot safer as a hydrogen storage medium than other alternatives in terms of shock resistance for example. He is also correct that it usually requires a lot of heating energy to release the hydrogen gas from the hydride and that has always been a stumbling block. So the conclusion is this technology is likely a long way from being marketable, if ever, I personally think hydrogen cars are a complete non starter given electric cars have much more superior characteristics. You waste a lot less energy with electrics. Even if for whatever reason you want to eliminate gasoline, it makes a lot more sense to just use CH4 directly. It is readily available and is a lot more dense than hydrogen.

    One example of what the people in the Youtube channels he's quoting get wrong is the quotes the company which develops this product make about using sewage and other "greenhouse" waste gases as an hydrogen source. He claims CO2 has no hydrogen in it. Well duh. The company isn't talking about CO2. They are talking about METHANE GAS (CH4) which you can get from sewage and landfills. But like I said, I would just burn it directly. But for whatever reason people seem to believe the AGW agenda and that's the excuse companies like these use to push things like hydrogen storage on us.

    It is clear in his video that the platter/tape metal hydride "tech" is a scam. You cannot store the necessary volume of hydrogen
    using 2D (surface) and you need 3D (volume). Nowhere in his video does he show any ignorance about metal hydrides. He explicitly
    refers to them as storage tech and provides examples. Your critique is about style and not substance. Thunderf00t is very abrasive
    and that can be a turn off. But the scammers don't deserve any sympathy.

    Can you provide a link to the CH4 vs CO2 video you are talking about? I have not seen him make such silly mistakes and his general
    level is inconsistent with what your are attributing to him. CH4 from landfills is actually exploited in some places. That is easy to
    validate with a Google search.

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    Post  kvs Tue Dec 07, 2021 10:32 pm



    Second part that I missed. I big destroyer gun makes more sense than this crap.



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    Post  kvs Yesterday at 5:20 am



    Unlike with politics, for science some questions are show stoppers. The ludicrous excuses why no absolute microwave background
    could be measured by the Planck satellite proves it was a total failure and worse a fraud.


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