On June 08 2018 11:29 Emnjay808 wrote: Question for the flat-earthers or anyone who would like to indulge me: how do they explain tide shifts throughout the day?
The earth and the moon orbits around each other via the center of gravity which causes a centrifugal force that pushes an outward water rise on the distal part side of the earth while the gravitational pull of the moon causes the other tide rise on the proximal end. Seeing as this is only possible if the earth is to be round, how would this be explained?
I only ask because I’ve seen some theories on how the sun rises and sets with the flat-earth theory. And I would like to see their pov of this as well.
Thats not how tides work btw. Tides exists due to the difference between the gravitational forces of the moon acting on Earth.
I kid you not. Everything you have been taught is a lie.
It's a wide spread fantasy propugated by badly written books just like how apparently wings work because of difference in air speed between the upper and lower sides of a wing.
The centrifugal force explanation is basically on the same level as flat earther tide theory. Uses scientific words to make the explanation sound plausible to the layman.
I'm not claiming to be a physics expert at all, or even to have a good grasp on mathematics (I know fundamentals, I understand concepts, but I'm severely lacking in the field) BUT there's something I've been wondering about.
What if the physical limits of the universe - light speed being the most obvious one here, at 300 000 km/s - are used in equations of motion as the actual upper limits in equations pertaining speed/... Let's say a formula deals with speed and has in infinite in it; or a formula regarding energy, which could have a speed factor in it, why not exchange the infinite for an upper limit, like c for example? Now, here's where my ignorance comes into play: I don't know of any properties or relations or formulas intricate/complicated enough which factors in infinities like that.. So IF there are any, why not go for my suggestion?
I might be able to help you here, but i am uncertain regarding what you are currently talking about.
If i understand you correctly, than that already exists: Formulas dealing with speed and having infinites in it (Or more exactly put, non-bounded variables, you don't actually put infinites into formulas usually) would basically be all of classical mechanics, and formulas dealing with speed with an upper limit of c are those based in special relativity.
Would you mind explaining a bit more what you mean if that is not what you are talking about?
Let's take a most straightforward example to illustrate my point, but it doesn't really make sense because the assumptions in my statement are wrong, but I guess it illustrates my point...
v = ds/dt; if your change in time is infinitesimal over a finite change in distance, or your change in distance is infinite in a non 0, non infinite time interval, your speed would become infinite. But if you adhere to the laws of physics, this value should only ever be c, even though it would be infinite mathematically speaking (please don't judge me too harshly lol).
So I wonder if there are more complex equations, or solutions of equations where instead of it resulting in an infinite, or while cases are made with infinities to come to a solution (which may or may not be an infinite) and if they actually should ever use infinity to solve something. Does that clarify it?
And you are correct, those equations exist. They derive directly from the principles of special relativity. The thing you need to realize here is that the limitations of the equations you usually use to describe stuff. Equations like Ekin = 0.5*m*v² are special cases of the more general equations. These equations which describe classical mechanics work very well under certain circumstances, namely when talking about stuff which is not too fast and not too tiny. But if you are outside those bounds you need completely different theories to describe the physics in place. If you are talking about very small stuff, that is quantum mechanics, and if you are talking about very fast things, it is special relativity.
For example, according to special relativity, the kinetic energy of a moving particle is not described Ekin = 0.5*m*v², but through Ekin = mc²/Sqrt(1-v²/c²) - mc².
As can easily observed, this equation is only defined for velocities smaller than c, and the kinetic energy necessary to accelerate something approaches infinite if you approach c. Meaning no matter how much energy you use to accelerate something, it only gets closer to c, but will never achieve lightspeed (As long as the thing in question has mass)
However, if the thing you are talking about is not very fast with regards to c, you can use a taylor expansion to approximate this more complex equation as the classical equation of 0.5*m*v².
This factor of 1/sqrt(1-v²/c²) is called a relativistic gamma factor and appears quite often in relativistic mechanics. Similar effects and similar equations appear when talking about relativistic mass, relativistic momentum etc...
If you are really interested in this, take a look at special relativity and how it works.
As another point, there are equations which describe stuff that we know of, but also lead to additional solutions which we have so far not been able to observe in reality. This can be as simple as an equation for throwing a ball producing two solutions of when it will hit the ground, one of which at a negative point in time. In these cases, one needs to filter the results to figure out which ones are the physically correct ones. But in more complex cases, it is not certain whether the additional solutions exist, and we haven't observed them yet, or whether they are simply artefacts of the mathematical way we use to describe things. Equations like v = ds/dt lead to solutions with velocities higher than c, but if one takes a look at the kinetical energy equation described above, these only work for imaginary energies or imaginary masses. Which is weird. So theoretically, stuff could move faster than light and still be compatible with special relativity, but that requires really weird circumstances which don't fit anything we have observed so far even remotely (And i mean really weird). But those theoretical particles are called tachyons.
I was golfing last night and I used the bathroom there which had a "not potable water, do not drink" sign which made me think.
I had just peed, there was no soap. My hands were relatively clean before I went in. Would soaking and rubbing them in non potable water make them cleaner or more dirty?
The whole "washing after going to the toilet" thing is kind of weird. Afaik it doesn't make a lot of sense as long as you only pee, and is mostly based in the cultural "pee = icky". Things become different if you defecate and use your hand to wipe, even if using paper, because there are a lot of bacteria in poo which are good in there, but not good at basically any place else. Pee is usually pretty clean with regards to bacteria, though it does contain other stuff that you probably want to have outside of your body. Which isn't a problem as long as you don't start drinking it. If anything in it were really toxic, you would have had that problem the first time it went through your body.
If anything, you should probably wash your hands before peeing. Because your genitalia are a lot more susceptible to infections than most other parts of your body, and hands are usually pretty dirty.
That being said, culture basically dictates you wash your hands before leaving the bathroom no matter what you did in there.
Dunno. I don't think washing your hands with water and without soap actually does a lot anyways with regards to hygiene. It obviously removes rough dirt like sand, but it doesn't really kill the bacteria. Related, "anti-bacterial" soap is a scam. If it says something like "kills 99.9% of bacteria", that is true of basically any soap.
I am not certain how good or bad non-potable water is.
On June 15 2018 02:31 JimmiC wrote: Does the water being not potable make a difference?
Not unless you are planning to lick your hands afterwards. Water cleans your hands by rinsing particulate off them. Soap aids this process by "dissolving" residue that might be clinging to your skin, especially if that particulate or residue is hydrophobic. Soap reduces water's surface tension, making it more able to wash away such matter. You can imagine a lot of reasons that water might not be potable: pathogens, chemical contaminants, heavy metals, etc. Let's say the water has a lot of iron oxide in it or something, making it unsuitable for drinking, but still usable for watering plants or washing dirt off things. You might even use it with soap to wash your hands clean of dirt and bacteria, even though you wouldn't want to drink it. The iron oxide particulate that ends up on your dried hands is not a very big threat and might be preferable to whatever else you had on them, especially if you were just shitting and wiped your ass.
If tomorrow, all the birds collectively waged war against mankind, who would win? I'm talking coordinated poop-bombing runs on critical structures, outdoor attacks on people, taking down power-lines, deliberate destruction of our food supply etc. How many casualties would this bird war bring? How would we stop them? Would guns be enough, if you're being swarmed by birds from every direction?