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Sensei

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Everything posted by Sensei

  1. Poor students use summer break to earn money for the rest of year.. (which disallows them to fully recover after year at school)
  2. Quality of study is more important than length of study. But if somebody is overloaded with work, increased time, might help him/her finish it. If somebody remembers answers for exam, and the next day, week, or month, forget everything, it's pointless education. Student has to remember knowledge. Only in the worst case, remember how to regain it, searching net, or books.
  3. There is no money on the Earth to help somebody fix their mental problems after horrible trauma..
  4. If you divide acceleration on the surface of some cosmic object by Earth's surface gravity acceleration, you receive dimensionless fraction or multiply of g. 1.62 m/s^2 / 9.81 m/s^2 = 0.165 It tells how much weaker or stronger is gravitation relative to Earth. Similar like if you divide distance from some planet by distance from Sun to Earth, ~ 150 mln km, you receive distance in A.U. (Astronomical Units). 1 AU = ~ 150 mln km
  5. How about experimental physics.. ? You can build Cloud Chamber for less than $50 by yourself. https://en.wikipedia.org/wiki/Cloud_chamber And then observe decays of radioactive isotopes, observe highly accelerated electrons, muons, pions, kaons, created by cosmic rays, passing through device.. Gold foil (Rutherford) experiment replicated in Cloud Chamber https://en.wikipedia.org/wiki/Geiger%E2%80%93Marsden_experiment
  6. Nuclear bombs don't "hit Earth". They have the largest destructive effect when they are exploding couple hundred meters above surface. Nuclear bomb is utilizing fission of unstable isotopes, which release large amount of energy. Which has nothing to do with asteroids or comets. They don't contain significant amount of fissile materials.
  7. Small correction (sorry), multiply above by 10. Earth's density is 5514 kg/m^3 and Moon's density is 3344 kg/m^3
  8. 1.6g would be stronger than Earth's gravitation. "Surface gravity 1.62 m/s2 (0.1654 g)" https://en.wikipedia.org/wiki/Moon You're searching for tidal locking. https://en.wikipedia.org/wiki/Tidal_locking
  9. Your party program sounds fine. But you didn't include in this education. Free of charge high quality education for everybody. That's key for having modern, equal, intellectual and technological advanced society. Your party program will upset a lot of lobby groups, starting from gas & oil industry, weapon producers, soldiers and ex-soldiers.
  10. I am seeing there "Normalized Chlorine-36 counts". Normalization in this context will mean process of dividing local quantity by average quantity. Suppose so you have decays between 900 to 1100 per some period of time (second, day, year). Average of it will be 1000. 900 divided by 1000 = 0.9. 1100 divided by 1000 = 1.1. Some scientists are detecting change of rate of decay of unstable isotopes http://physicsworld.com/cws/article/news/2016/nov/24/do-solar-neutrinos-affect-nuclear-decay-on-earth " In recent years, however, there have been suggestions that decay rates are not constant and are influenced by the Sun. In 2009, physicists from Purdue University in Indiana published a paper discussing unexplained annual fluctuations in long-term measurements of decay rates of silicon-32 and chlorine-36 at Brookhaven National Laboratory (BNL) in New York and radium-226 at the Physikalisch-Technische Bundesanstalt (PTB) in Germany. "
  11. This equation can be written as: [math]E=m_0 c^2 \gamma[/math] [math]\gamma = \frac{1}{\sqrt{1-\frac{v^2}{c^2}}}[/math] when v=0 it simplifies to [math]\gamma= 1[/math]. giving: [math]E=m_0 c^2[/math] Annihilation of matter-antimatter. Pair production. Decay of unstable particle (lepton,meson,baryon). Suppose so you have gamma photon with energy 1.5 MeV. It's slightly more than required for pair production (electron-positron) 1.022 MeV. But energy has to be conserved. So you have: [math]E_{src}=1.5 MeV[/math] [math]E_{dst}=m_e c^2 \gamma + m_e c^2 \gamma[/math] [math]E_{src}=E_{dst}[/math] [math]1.5 MeV=m_e c^2 \gamma + m_e c^2 \gamma[/math] 1.5 MeV - 1.022 MeV = (approximately) 0.5 MeV And it's double kinetic energy of electron-positron. So each will have K.E. = 0.25 MeV (calculate gamma for it as exercise) [math]KE=m_0 c^2 \gamma-m_0 c^2[/math]
  12. 4+ millions years ago there was no human on the Earth.. So, who was observer instead.. ?
  13. Now you have answer: https://www.bloomberg.com/politics/articles/2017-03-16/trump-proposes-historic-cuts-across-government-to-fund-defense
  14. Absolutely not. But half of US citizens truly believe in it, otherwise they wouldn't vote on DT, so I am just suggesting them IMHO better solution instead of wall..
  15. Can't you be more merciful for David?? He is not very good at English, nor programming.. But he's trying to be useful and helpful member of this community. I will up-vote his post, even though it has error. But it's error because of not understanding OP problem. ps. Can't you be more MERCIFUL.. ?
  16. Solar system (Sun system) is one (at least in this version of Universe), in which you're currently inside. Star systems, with other planets (called exoplanets ) are many. https://en.wikipedia.org/wiki/Star_system
  17. That's very large simplification. If US investor is investing his/her money in Mexico, creates jobs in Mexico, these people remain in Mexico, and don't flood USA as emigrants. So, by his/her action, even unintentionally, he/she is doing something good for USA. Decreasing rate of emigration.. How to have flood of Mexicans on the border to US, and have serious emigration problem.. ? Make a law disallowing US citizens investing in Mexico.. How to solve emigration from Mexico problem? Invest, and hire them in newly created companies in Mexico..
  18. USA is wasting tremendous amount of money on army and wars.. And now you will be wasting money on the wall with Mexico..
  19. Wrong solutions, and too late. Kids don't pay taxes to have tax breaks.. Current obesity problem in US/UK starts in early stage of kid life. Karate, tae-kwon do, kung fu etc. obligatory lessons since primary school, instead of normal PE Phys. Ed. Initial year of karate exercise 3h (1.5h x 2 days) per week. On karate lesson everybody are training simultaneously. On normal PE lesson only the best players are playing (team games), while nerds, geeks, obese are just stareing from bench.. They are excluded by good players to not lose.
  20. The more interesting would be actual statistical data, how much money from how many taxpayers these extreme taxes were bringing to the budget in the past.. If somebody is smart enough to have such legal earnings, is also smart enough to bypass them (either legal way or illegal way).. How much is 91% from 0.. ? It's less than 10% from $1 million.. Absolutely not. It's encouragement for people to cheat, and do everything to bypass it.. Poverty should/could be fight by free of charge high quality education. Model in which people have to pay for education, is promoting rich people to gain education, and rejecting poor people.
  21. You, or I, could be hit by a bus. Or (as happened to two relatives) drop dead completely unexpectedly. I choose to believe that won't happen. There is approximately 7.5 billion people on the world, and ~ 150 thousands of people die per day. https://en.wikipedia.org/wiki/Mortality_rate So average chance to die tomorrow is 150k / 7.5 bln = 1:50000 But the real chance to die changes with time, region of world, as a result of actions or lack of them, unhealthy life style, unhealthy job, risky hobbies, lack of medicament/vaccination.. etc. etc.
  22. That's true that high profile generals have plans to attack, or defend against, any imaginable enemy.. But I was talking about ordinary people.. So, US generals also must have ready plans to attack Mexico, on their the most secretive shelf.. Connection between Ukrainians and Russians could be compared to connection between New Yorkers and Los Angels people... Ukraine used to be part of USSR for half century.. Previously the were part of Poland since XV century (up to 1794 year).. That's true. But attack on Georgia, and attack on Ukraine, are separate events.. Unless you suggest they are connected, larger plan that's ongoing for at least 10-20 years.. ? Then if you're so well informed, tell us in advance what will be the next target.. ? Georgia used to be country in ancient Rome times.. https://en.wikipedia.org/wiki/Roman_Georgia While Ukraine is called "sessional country", according to history book I am reading right now.. (in comparison to eternity, every human made country, is just sessional)
  23. 5 years ago nobody in russia would believe they will start (and die in) war with Ukraine..
  24. If there would be no nuclear weapon, recent russian attack on Ukraine, almost certainly would result in conventional war between Europe/USA and russia, like it used to be in the past, prior making atomic bombs.. There is no way russia could manage to win conventional war, even with part of European countries. Now everybody are afraid of counter-attack, using nuclear weapons, in the last stage of war, which paralyzes their reactions. Reaction should be strictly targeted at people responsible for aggression, not at entire country population (which always suffer the most while conventional/nuclear war). People should not be afraid of getting rid of politicians which can kill entire human race, large population of some nation, or starting senseless war for nothing (like in the above example, attack on Ukraine. Russia needs more land? Needs more resources? Ridiculous).
  25. Argument for your thesis: - social media consuming people's time, on stupid things, like constant making selfies every couple minutes and commenting "friends" photos.. etc. etc. Argument against your thesis: - easy access to knowledge, now people don't have to have paper encyclopedia, everybody can search net/wikipedia, for information that they need. It is/could be the most important for 3rd world country people.
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