Wow. Thanks for your explanation.

I can sorta see the picture now.

RTG's also tend to use isotopes with a much shorter half-life (since they decay faster and produce more energy). So while they can last years/decades, they don't last the centuries/millenia of nuclear fuel.

The company I worked for had designed all of our PCBs, (printed circuit boards) using switch mode power supplies without integrated components. Essentially, we had to add the coil, capacitors, resistors, etc… to define the characteristics of the supply. It just so happened the parts we selected caused the frequency the system operated at to be in the audible range. It caused an audible hum or whine, when operating.

To alleviate our issues, we selected different values of components that in the end achieved the same output characteristics, but at a higher operating frequency to prevent the hum. Pretty minor fix and everything else was the same except for the operating frequency so the hum was gone.

When you run a current through a wire it creates a magnetic field. Flip that current on and off real quick and you'll get a vibrating wire. Coil that wire up real tight to make an inductor and now you've got a thing vibrating at a high frequency and possibly having an audible frequency getting kicked off

Coils vibrate, it's just what they do. Normally they're running at hundreds of kilohertz to megahertz so it's way beyond audible range but sometimes it makes the core rattle at an audible frequency, but it's hard to fix by winding differently

Common solutions are a big dollop of hot glue(yeah, just normal hot glue, it's cheap) or dipping the coil/transformer in varnish (clear nail polish). Both solutions just bind things together better so they can't move/vibrate as well

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By now, in most places around the world there are laws in place to mandate a minimum efficiency for power supplies. To achieve the mandated efficiency, manufacturers use so-called switching power supplies, which are based on quickly switching electronic switches on and off and using the energy "storage" characteristics of coils (current) and capacitors (voltage). Under certain circumstances, those switching frequencies or harmonics thereof (harmonics=base frequency multiplied by a whole number, but sometimes also divided) fall into the audible range. The magnetic fields changing over time cause forces changing over time on the metal loops of the coil, making them want to move in sync. If nothing prevents them from moving and if, by moving, they somehow hit each other or are massive enough to move enough air to be heard, you get the whine. Sometimes capacitors can also whine because of something called piezoelectric effect.

It can be alleviated by careful choice of switching frequency and coils and capacitors, although perfect silence in all conditions often isn't a top priority in design. Coating the coil can also help, but the used material needs to be as transparent as possible to the magnetic field and could inversely affect thermal dissipation.

There's really nothing you can do about it. It's based on build quality and the components the manufacturer chose. Some people have had luck by putting silicone sealant into the coils, this obviously voids your warranty.

Tectonic plates are HUGE and move slowly, which would be akin to very slowly bending a plastic ruler. You can keep bending it for a long time and nothing will happen until it reaches the breaking point and shrapnel flies everywhere

Simplest visualisation is snapping your fingers. Your thumb and middle finger are the tectonic plates, pushing against each other until the force trying to move them becomes stronger than the friction keeping them in place and then SNAP earthquake.

>To reduce coil whine, it is important to ensure that components are properly secured and that the laptop is running at the manufacturer's recommended frequencies.

As a regular laptop-enjoyer, how exactly am I supposed to check that the components are properly secured?

Coil whine is a high-pitched noise that is caused by electrical current flowing through the coils of a laptop's power supply. It is usually caused by components vibrating due to the current and can be heard when the laptop is in use. It is often caused by poor manufacturing and design, as components can be poorly soldered or not properly secured. It can also be caused by components running at higher frequencies than they were designed for. To reduce coil whine, it is important to ensure that components are properly secured and that the laptop is running at the manufacturer's recommended frequencies. It is also important to ensure that the power supply is of good quality and that the laptop is running at the correct voltage.

So basically, when the tectonic plates move, they can get stuck and build up a lot of pressure. Once that pressure becomes too much, it causes the plates to suddenly shift and release a ton of energy, which is what causes an earthquake.

It's a blanket term for all EM-induced vibrations that lead to audible noise, and generally yeah it's something you either want to avoid or mitigate with sound dampening materials.

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Thank you

Earthquakes are caused by the sudden release of energy that has been stored in the Earth's crust. This energy is built up over time as the tectonic plates move and interact with each other. This movement is slow and steady, but when the pressure between the plates reaches a certain point, the plates suddenly slip, releasing the stored energy in the form of seismic waves. These waves travel through the Earth's crust, causing the ground to shake and resulting in an earthquake.

Atoms have a certain number of electrons in their outermost shell, and this number determines the type of chemical bonds they can form. We know that atoms can't have more than 8 maximum outermost electrons because of the octet rule. This rule states that atoms will always try to fill their outermost shell with 8 electrons in order to achieve a stable electron configuration. This is why atoms prefer to form chemical bonds with other atoms that will give them 8 electrons in their outermost shell. Research is being done to understand why atoms prefer the octet rule. Scientists are studying the electronic structure of atoms and molecules to understand why the octet rule is so important for chemical bonding.

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That makes a ton of sense, had always wondered why shows got cancelled and then would ultimately continue. Seems like this happens more lately because networks see this as a major source of cost savings and now use it routinely as a tactic.

When you make a TV show you have a contract with one network. However after you reach a certain number of episodes, usually 100, your show can then be shown on other networks, which is called syndication. So for example Law & Order ran on NBC, but because it entered syndication reruns are shown on a bunch of channels.

The reason that people want a show to reach syndication is because you can make a lot of money. In fact there are a number of shows where actors make more money from syndication than they did from the show. There's two ways this happens. The first is that the Screen Actors Guild (SAG) has what is called a "residuals schedule," basically an agreement about how much actors get paid for reruns. This is around 6% of your salary per episode. So, for example, the principal cast of Law & Order each make around $200,000 a year from residuals, which is good money.

The second way is that you can have part of your contract say that you are entitled to royalties, which is even more money based on the success of the show. For example the six principal stars of Friends each make around $20 million a year just from reruns and Jerry Seinfeld has made more than $400 million from Seinfeld reruns.

I think the short and boring answer is 8 electrons can arrange into 4 electron pairs, which gives you tetrahedral symmetry with the atom in the center and its bonds extending towards the corners of the tetrahedron. As an example, CH4 has this structure. For many atoms, 4 outer electron pairs seems to be optimal in sense that atoms still can get close enough to share electrons without bumping to each other, and the pairs can still arrange into structures called orbitals where they can get as far as away from each other as possible in a deliberate way that is described by quantum mechanics.

When atom is floating alone in space, the orbitals are all distinct and create these quantum-mechanically allowed non-overlapping structures such as s, p and d orbitals, and so forth. When other atoms enter the picture, the situation changes and the orbitals are said to hybridize, which is to say that they are no longer like that but tend to combine and the picture is now more complicated. As an example, tetrahedral symmetry is result of 2 distinct orbital shell types combining together to yield this new structure of 4 identical covalent bonds.

First group elements tend to only create one covalent bond as their outermost shell is single spherical structure that can only fit 2 electrons, and they already have one themselves. Most other elements seem to prefer 8 electrons, likely because of the sweet spot of maximizing electromagnetic attraction with electrons and protons, while also still minimizing the electromagnetic repulsion between the electrons. Then there are transitional metals which are larger in diameter and create more complicated covalent bond structures, apparently between 12 to 18 electrons, and there electrons also make use of the d orbitals which tend to be more pointy and narrow in their shape, which is a general trend with all the higher orbitals.

Not really.

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But it is possible to have different forms of fission reactors that produce wastely less waste. It is even possible to recycle some of the waste we currently have and then reduce the time to decay

You see, we know how atoms work by solving very complicated quantum mechanics equations (in the past by hand!) And we could learn things like the orbital shape and other useful properties.

Now, solving everytime equations is hard and most of the time in chemistry there are a lot of shortcuts to make life easier. The octet rule is one of those, and if you look at the f and d block, or the haufbau filling rules you see that the octet is not so much set in stone!

Also, in the past by looking ad atom emission and absorption spectra we could find out quite accurately the energy of the levels, and it his way we can really see how electrons occupy atomic orbitals !

It's very important to understand that fission and nuclear decay is not the same thing. You cannot compare the two.

Consider that in nuclear physics there are "magic numbers". I can remember 2, 4 and 8 being some of them, but at the moment i can't remember the rest.

These numbers are linked to very stable layouts, against unstable ones.

(Tritium is much less stable than deuterium for example) I don't think we have a definitive explanation as of how and why they work, but rember (as a very basic intuitive approach) that an even number of things can be easily arranged in symmetrical ways, and some arrangements are much easier to obtain than others (for example there are 8 evenly distributed vertices in a cube)