Ask any question you want about Physics

darn the witnesses are in on the trick
a reply to: Soylent Green Is People

a reply to: Arbitrageur
Thank you for your effort and insight! I will post this in the other thread for others to consider.

ETA:

The higher frequencies in 5G can't penetrate as far.

To accommodate this they will supposedly put antennas everywhere(mesh configuration) for continuity of signal(s) throughout coverage area. Will this increase any negative effect? When IOT rolls out it seems the signals will saturate and overlap in areas.
IOT antennas

originally posted by: waftist
To accommodate this they will supposedly put antennas everywhere(mesh configuration) for continuity of signal(s) throughout coverage area. Will this increase any negative effect?

The question is what are the possible negative effects?

Power levels won't be high enough to burn the skin like the crowd control devices. They probably won't be high enough to feel an effect on the skin but even if they were, it would be a warm sensation. If you felt a little chilly in the winter time and that made you feel a bit warmer, that could actually be a good thing, right?

In the summer when it's hot you don't want to feel any warmer so to the tiny extent it warms your skin, the worst I can see is adjusting the air conditioner so you feel more comfortable.

But I wouldn't really expect people to feel anything from the 5 G due to the low power levels, I was just comparing it to the crowd control devices for reference.

As I said I don't know if skin cancer is a possibility of long term low exposure to 95 GHz. One study says skin cancer is not a problem from 94 GHz frequencies, but from the variation in results of the 4G studies I'm not inclined to feel extremely confident about just one study. So maybe we are human guinea pigs to some extent in that skin cancer aspect but frankly it's not on my list of concerns.

There are many other risks we face that are far more likely to harm us or kill us, so threats from 5G are pretty far down my list and to the extent they are on my list at all, they are exactly the same threats we have from 4G where people hold the phone closer to their heads than the instructions from the manufacturer allow (because 5G can use the same, more penetrating frequencies as 4G). I know about those instructions, but keeping my phone that minimum distance from my head is easier said than done, especially if I'm in a noisy environment and the other party isn't talking too loud, where I probably get my phone too close to my head sometimes, closer than the instructions allow.

In the recent past I had watched a video of a female prof from new York( Lol she looked exactly like one of my girlfriends) who claimed to be the classmate of prof brian green. In the video she said that dark matter is everywhere, even in our bodies. If so, what are the ways that, this dark matter can be detected? Tho I cant quite remember her name

yes the current theory is that if the Galaxy is moving within a dark matter halo, then dark matter is present in particulate form everywhere at all times. So much like neutrinos from the sun pass through us all the time, dark matter does the same.

We are still attempting to detect it with specialized detector systems, so, one step at a time

originally posted by: ErosA433
yes the current theory is that if the Galaxy is moving within a dark matter halo, then dark matter is present in particulate form everywhere at all times. So much like neutrinos from the sun pass through us all the time, dark matter does the same.

We are still attempting to detect it with specialized detector systems, so, one step at a time

She didn't say anything about galaxy moving thru any dark matter halo, although if I remember correctly she talked about dark matter being reason for mass of matter, which is my opinion too

a reply to: Arbitrageur

I have a question that I would love answered.

Why does water flow down a hole in the northern hemisphere anti clockwise and clockwise in the Southern Hemisphere? I saw an experiment where this affect was demonstrated just 10 yards north of the equator and then 10 yards south.

I’d assume it has something to do with the earths magnetic field but magnetism has no affect on water right?

Thanks in advance.

It's due to the coriolis force
a reply to: surfer_soul

a reply to: Hyperboles

From what I understand the Coriolis force is due to the difference in speed of spin between the equator and the poles. So why in the experiment does it work when done so near either side of the equator? The distance was only twenty yards of separation, I wonder which way water would rotate when pouring right over the equator?

Thanks for the reply it seems right just very odd in regards to the demonstration I remember I’ll look into more.

a reply to: surfer_soul

The coriolis acceleration is the cross product of earth angular velocity vector (earth rotation axis) and flow velocity vector.

At the equator for water flowing horizontal on the surface the acceleration would be either zero or vertical, would not create vortices. But if it flows down a slope/funnel you would get a horizontal component.

On the other side I've seen videos of two kitchen sinks next to each other having counter rotating flows. So the coriolis effect is apparently pretty weak. The swirls can arise from small disturbances and self reinforce.

originally posted by: surfer_soul
Why does water flow down a hole in the northern hemisphere anti clockwise and clockwise in the Southern Hemisphere? I saw an experiment where this affect was demonstrated just 10 yards north of the equator and then 10 yards south.

If they used sinks to demonstrate it, it was probably a hoax or a trick.

originally posted by: moebius
On the other side I've seen videos of two kitchen sinks next to each other having counter rotating flows. So the Coriolis effect is apparently pretty weak. The swirls can arise from small disturbances and self reinforce.

Correct, it's actually a myth that the Coriolis effect determines whether sinks or toilets will form vortices in one rotation or the other; the reality is as you said, you can have two sinks right next to each other which drain with opposite vortices because the Coriolis effect is too weak to overcome other, random variables.

There is no exact cutoff for the size of the body of water that would be so affected since there are various random effects of various magnitudes competing with the Coriolis effect, but generally the larger the body of water, the more reliably it will drain in the direction influenced by the Coriolis effect. Snopes busted this myth:

Claim: Water in a pan, sink, or toilet rotates counter clockwise in the northern hemisphere and clockwise in the southern hemisphere. This is due to the Coriolis Effect, which is caused by the rotation of the Earth.

Status: False

Reality: the Coriolis effect is so small that it plays no role in determining the direction in which water rotates as it exits from a draining sink or toilet. The Coriolis effect produces a measurable influence over huge distances and long periods of time, neither of which applies to the typical terrestrial bathroom.

Maybe someone saw the rigged demonstrations near the equator set up for gullible tourists?

The belief that the Coriolis force influences the direction in which water drains from plumbing fixtures is widespread and has been repeated as fact in a number of venues, including popular television shows (such as world traveler Michael Palin’s Pole to Pole series) and even in textbooks. It’s also been promulgated by any number of hucksters who set up rigged demonstrations along the equator for the amusement of gullible tourists:

Ecuador At The Equator - Water Demonstration - Coriolis Effect


That's a hoax or a trick, this site explains how the trick is done:

Flushing out an equatorial fraud

However one disagreement I have with the snopes article is that it says you won't see the Coriolis effect in a pool. In a ~2m diameter kiddy pool, it's still a bit small and an even larger pool like an olympic sized pool might be large enough to allow the Coriolis effect to determine drain direction reliably. In this video you can see the effect is extremely tiny in a kiddy pool and had the experimenter not gone to extreme measures to eliminate other variables, it might not reliably drain in the direction expected from the Coriolis effect.


So watching how the dye barely rotates in the kiddy pool in that video gives you some idea of how small the Coriolis effect is on a kiddy pool. Other people draining kiddy pools without going through the extreme measures in that video to eliminate other variables might not see a reliable correlation of drain direction with the Coriolis effect. If the body of water is say 10 meters in diameter then you might start to see a reliable correlation without the extreme care to eliminate other variables.

a reply to: Arbitrageur

I was just sitting last night and suddenly I started thinking about tectonic plates and tsunamis
and how we could stop them from causing so much devestation

I immediately thought of the process of how these occur , and thought ok its about displacement by tectonic plates of large volumes of water!

So the wave itself would need to be reduced in energy and size
and so you'd think you'd need a wall or barrier to break it
The water itself came from a shift in tectonic plates either up or down causing the water to form a wave
what if you had a barrier that not only harnesses the wave energy
but somehow gives it a place to go back to ?

AS in how to move the water from a wave back to the sea
I dont know why but I thought what if you created another displacement of water
what if you were to detonate small explosive controlled charges along the wave front , would this create a pocket of air large enough to displace the wave ?

Could this be used to stop tsunamis , Im just trying to think of the pyhsics of it , can a wave be displaced by removing the water underneath it or in front of it causing the water in the wave to suddenly fill the pocket created by the explosion ?
Could this energy then be transfered into wave generators ?

No idea why I suddenly started thinking about this !

Anyways just a random thought

a reply to: sapien82
I have this article that I was going to post in the Japan board to show how preventable the Fukushima Nuclear Plant disaster was, but I never did so I'll post it here:

IAEA: Nuke plant near Fukushima largely undamaged
The first problem with your explosion idea is that a tsunami isn't one wave, it's a series of them, and I can think of many more so it's likely not feasible, but even if the first explosion worked (which I doubt, or could even make things worse), the area would still be evacuated so who would be around to lay the charges for successive waves?

But we already know a seawall can work. The plant that had the meltdown, Fukushima Daiichi, cut costs on plant construction and also on seawall construction. Another nuclear plant in Japan at Onegawa was a lot closer to the epicenter of the earthquake and got hit by at least as large a Tsunami, but they didn't cut costs on construction of the plant or the seawall, they built both with safety in mind instead of cost-cutting, and had no meltdown, for a number of reasons, but in part because the seawall worked.

The Japanese nuclear power plant that was closest to the epicenter of last year's earthquake suffered more ground shaking than Fukushima but was largely undamaged because it was designed with enough safety margins, nuclear inspectors said Friday.

The Onagawa plant in northern Japan recorded temblors that exceeded its design capacity and the basement of one of its reactor buildings flooded. But the plant maintained its cooling capacity, its reactors shut down without damage to their cores and there were no signs of major damage to crucial safety systems.

The U.N. nuclear watchdog's inspectors found the Onagawa plant managed to avoid a catastrophe like Fukushima because its safety systems "successful functioned," said Sujit Samaddar, who led the 19-member International Atomic Energy Agency mission.

"With the earthquake of this magnitude, we would have expected the plant to have more damages, and that was not the case," Samaddar said. "This indicated there were significant margins in the designs."

In contrast, the 9.0-magnitude earthquake on March 11, 2011, knocked out a power line at the Fukushima Dai-ichi plant and generated a large tsunami that flooded its emergency generators, destroying the plant's cooling systems. Catastrophic meltdowns occurred in three reactors, releasing radiation that has tainted the surrounding environment.

This part discusses the seawall specifications:

The Onagawa plant was about 70 kilometers (44 miles) from the quake's epicenter, while Fukushima Dai-ichi was nearly 180 kilometers (112 miles) from the epicenter. Onagawa is about 120 kilometers (74 miles) north of Fukushima Dai-ichi.

The tsunami was more than 13 meters (43 feet) high at both nuclear plants. Fukushima Dai-ichi's seawall was built to withstand a tsunami of up 5.7 meters (18.7 feet). Onagawa's seawall was nearly 14 meters (46 feet) high and survived the tsunami. It has since been extended to nearly 17 meters (56 feet) above sea level.

I imagine the costs of building a seawall 14m or 17m high are substantial but they are surely essential to protect nuclear plants on the coast near fault lines. Whether Japan can afford to build them more extensively along the coast is questionable, but compared to the cost of reconstruction of all the devastation maybe the cost doesn't seem so unreasonable.

The sad part of the Fukushima Daiichi disaster is that Tokyo Electric Power's own people told them three years before the disaster their seawalls weren't high enough, and somehow several decades before that the Onegawa plant designers already built a much higher seawall to protect from such a large tsunami.

I remember one article in Japan after the Fukushima tsunami where a reporter went up a hillside near the coast and found a centuries old stone marker which was the high point of a previous tsunami, with a warning not to build anything below the marker because a tsunami will wipe it out. Of course the marker was ignored and there was huge development below the marker, but that would be the alternative to the seawall, to build on higher ground further from the coast and leave the hazardous coastal region relatively undeveloped or at least consider anything built in low coastal areas without a big seawall is expendable and don't expect it to survive a tsunami.

So bottom line, if you build a big enough seawall, it seems to work. In the absence of seawalls, just don't build anything in low lying coastal areas you can't afford to lose, seems like the best way to avoid devastation, if there's nothing there to get devastated.

One example that comes to mind is Hilo in Hawaii, and specifically the bayfront community called Shinmachi which was destroyed by a tsunami in 1946. Shinmachi was completely destroyed again by another tsunami 14 years later in 1960, but they got smarter this time and didn't rebuild it. Instead it was converted to a park, so there was no Shinmachi to get destroyed again by the next tsunami which came in 1975.

a reply to: Arbitrageur

Hey ARbitrageur

thank you so much for your reply and taking the time out !

I was just wondering say you had these wave generators sitting on the water in the bay for example or just out at the sea after the breakers

would you be able to create some sort of controlled implosion or explosion from these generators underneath the surface to create pockets for the water to fall into and at the same time harness the energy of the waves themselves

I just wanted to know if it is physically possible to do this , by creating another empty pocket of space in front of the advancing wave would this actually work to stop the wave ?


Or would creating this pocket only serve to add more energy to the advancing wave ?
I was just thinking in terms of its energy how to dissipate that rapidly

a reply to: sapien82
It wouldn't be economical to do and you could take some energy out but probably not enough.

A rough analogy to consider is a hydroelectric power plant which generates electricity from water falling from the dammed up lake.

The amount of kinetic energy in the falling water is reduced by the electric generators as the water falls, but it's not reduced to zero. It's economical to build these generators because you can get a fairly consistent flow of water unless there's a drought or something.

It wouldn't be economical to build tsunami generators because of the rarity of tsunamis, and even though the water isn't falling, the wave is being propelled toward shore, so like with the dam generators you could take some energy out of it but probably not enough and it would keep coming albeit with lower energy (the energy you converted to electricity would be removed).

Those hypothetical tsunami generators will never happen because it's just not economical to build them due to the rarity of tsunamis. However what is much more likely to succeed are tidal generators, that extract energy from the daily ebb and flow of water due to the twice daily tides. The US doesn't have any tidal barrages, but South Korea and France have Tidal barrages that generate 254 MW and 240 MW respectively, already in operation. Here's a link which mentions them and some other tidal power concepts:

Tidal power

Several tidal power barrages operate around the world. The Sihwa Lake Tidal Power Station in South Korea has the largest electricity generation capacity at 254 Megawatts (MW). The oldest and second-largest operating tidal power plant is in La Rance, France, with 240 MW of electricity generation capacity. The next largest tidal power plant is in Annapolis Royal in Nova Scotia, Canada, with 20 MW of electricity generation capacity. China, Russia, and South Korea all have smaller tidal power plants.

The United States does not have any tidal power plants, and it only has a few sites where tidal energy could be economical to produce. France, England, Canada, and Russia have much more potential to use tidal power.

As for your wave generator idea, I think I understand the concept would be to try to cancel out the incoming waves, maybe along the lines of how noise cancelling headphones create waves with destructive interference? The question is, how do you do that without the wave you generate being just as big and with the same wavelength? In an earthquake generated tsunami, the wavelengths can be 20km to 200km long, so it becomes extremely difficult to generate waves with such a long wavelength without another earthquake. Even if you did, wouldn't it tend to propagate in all directions from the source? In that case, you'd need a seawall to protect the shore from your wave generator, so why not just skip the wave generator and use the seawall, which would be a lot less complicated?

And if you didn't match the wavelength, then yes it would make things worse because the wavelength mismatch would mean you'd have destructive interference and constructive interference at different points, constructive interference meaning your generated wave being added to the tsunami.

It's a lot easier to generate the audio frequencies that noise cancelling headphones use!

Ques

Has anyone successfully linked gravity and magnetism together?
These are linking it is this history channel video on ancient aliens
www.youtube.com...

a reply to: Hyperboles

Ancient astronaut theorists contend ...

It is so sad. There was a time when History channel was about history. Now its mostly unsubstantiated and sensationalized pseudodocumentaries.

a reply to: moebius

Yes but some of the speakers have a good standing

another from history channel

a reply to: Hyperboles
There's only about 7 pages left in this thread. Please allow on-topic posts on the topic of "Ask any question you want about Physics", and don't waste them with off-topic pseudoscience and pseudo-archaeology. Linda Moulton Howe who appears in that video doesn't have much credibility left as is the case with numerous other pseudoscientific guests. According to the following article, in the rare cases where a legitimate scientific guest gives the show a sound bite, it's often twisted or taken out of context, so they do little to add scientific legitimacy to the ancient aliens idea.

The Idiocy, Fabrications and Lies of Ancient Aliens

Ancient Aliens is some of the most noxious sludge in television’s bottomless chum bucket. Actual experts are brought in to deliver sound bites that are twisted and taken out of context while fanatics are given free reign. Fiction is presented as fact, and real scientific research is so grossly misrepresented that I can only conclude that the program is actively lying to viewers. To present the show as a documentary, on a non-fiction network, is a loathsome move by the History Channel spinoff. (Technically, Ancient Aliens airs on an offshoot of the History Channel called H2.) If the network and the show’s creators want to present Ancient Aliens as a light survey of fringe ideas and make it clear that the ideas aren’t meant to be taken seriously, I can’t quarrel with that. But Ancient Aliens and shows like it winnow away at actual scientific understanding by promoting absolute dreck. Ancient Aliens is worse than bad television. The program shows a sheer contempt for science and what we really know about nature.

The only thing I've seen related to that show that seems good is the meme mocking it, because the self-contradiction is funny:



I think it was around the 1960s that there seemed to be some research going on trying to link gravity and electromagnetism with terms like "electrogravitics" being used, but no link was found in the present state of nature.

One hypothesis or idea is that at high energies in the time frame of the big bang, there might have been a unification of forces. The electroweak unification theory is considered successful which unifies electromagnetism and the weak force shown on the left, but I'm not completely sure of the status of the other proposed unifications shown here. I don't think gravity has been unified with the other forces in any working model yet, even at high energies, but it's thought to be possible if we can ever figure out how to model it. We may be closer to a unification of electroweak and strong at high energies but I don't think that is quite done yet, though if anybody else has some insights on the other unifications besides electroweak, feel free to share them.

hyperphysics.phy-astr.gsu.edu...


Even if this illustration is anywhere close to being the right idea, it shows that unification of gravity with the other forces ended a tiny fraction of a second after the big bang.