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Justin

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I am a Software Developer and I enjoy helping people with mathematics or physics problems. The best part is that many questions introduce me to something completely new and then I have to do a lot of research to be of help. Post these symbols on your profile, lets make it possible for EVERYONE to use these symbols. Useful symbols (please copy and paste as needed): ∫ Σ → ∞ Π Δ Φ Ψ Ω Γ ∮ ∇∂ √ ∅ ° α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ σ τ υ φ χ ψ ω ⁰ ¹ ² ³ ⁴ ⁵ ⁶ ⁷ ⁸ ⁹ ⁺ ⁻ ⁿ ₀ ₁ ₂ ₃ ₄ ₅ ₆ ₇ ₈ ₉ ₊ ₋ ⅓ ⅔ ⅕ ⅖ ⅗ ⅘ ⅙ ⅚ ⅛ ⅜ ⅝ ⅞ ≡ ≈ ≅ ≠ ≤ ≥ · ~ ± ∓ ∤ ◅∈ ∉ ⊆ ⊂ ∪ ∩ ⊥ ô

  • Sun, could a super hero "swim" on the Sun?

    I've always imagined that if some kind of super hero or machine would go into the gas giants it would slowly fade away into the clouds. Kind of like when a plane goes into a cloud.

    I guess this is actually two questions, please answer both if you can.

    1) What about the Sun? Ignoring the blinding brightness, is there a discrete layer between sun-atmosphere and sun-surface like on rocky planets?

    2) could a super hero swim on the Sun or would he be sucked into the core because the sun material has no bouyancy?

    7 AnswersAstronomy & Space7 years ago
  • Chess PERMUTATION with 8 squares?

    If you like FUN MATH problems then please tough it out and read my long question. It is a challenge

    If you can't solve this then AT LEAST give me an upper bound. this isn't only for fun. I kinda need this for a program I'm writing for fun. lol

    In short " How Many Ways Can You Fill EIGHT Squares With Pieces From A Chess Board? Squares can also be empty." This isn't strictly a permutation or combination problem. It's a little of both.

    I know math questions like this need to be worded VERY carefully. I remember college math classes and how the math question could be interpreted as a permutation or combination problem so I'll be as explicit as I can!!

    Imagine 8 squares of a chess board. The order of the pieces will often matter but sometimes not. Pretend it is impossible to tell pawns of the same color apart. It is impossible to tell knights of the same color apart. Impossible to tell rooks of the same color apart, etc. hopefully you get where I'm going with this. However if you had 8 completely different pieces on the board then it would simply be 8! ways of arranging the pieces. But if you had 8 pieces and two of them were white pawns then that would change the answer because white pawns are indistinguishable from each other. Also remember that I am counting empty squares as "pieces". All empty squares are identical.

    White & Black each have 8 pawns, 2 rooks, 2 knights, 2 bishops, 1 queen, and 1 king. The empty square does not belong to a color.

    For the sake of keeping things simple follow the next few conditions

    1)Like pieces of the same color are identical as far as the math is concerned. What I mean is that if you put all 8 black pawns on the squares then I don't care how the pawns are arranged or the order they are placed in. The same goes for all white pawns. Or if you have two white rooks on the board I don't care if the rooks trade places. There is only 1 way to arrange 8 white pawns.

    Given 8 squares. How many ways could you arrange the pieces if you consider that empty squares are allowed.

    2 AnswersMathematics7 years ago
  • Noble gases, electron shell, how is it full?

    I've heard for years that the outer electron shell of noble gases are full. Thus they are inert. This is true, therefore something is flawed about my understanding of electron shells and how they are filled. The sources below give a good summary of how electron shells and their sub-orbitals are filled. All the noble gases have 8 valence electrons.

    First lets look at an element that I understand, Neon. The first suborbital fills with 2 electrons, and the 2nd shell with its "s" and "p" suborbitals can fill and have 8 valence electrons. And wouldn't you know that this is exactly what Neon does, so that makes sense. Now I look at Argon. It has an atomic number of 18. So the 1st shell uses 2 electrons, the 2nd shell uses 8. That leaves 8 electrons for the 3rd shell. The "s" and "p" suborbitals of the 3rd shell are filled leaving the "d" suborbital completely empty. That suborbital can hold another 10 electrons!

    http://www.chemtube3d.com/A%20Level%20orbitals.htm

    http://www.freewebs.com/ryanbchemistry/Images/Elec...

    2 AnswersChemistry8 years ago
  • When circuit "splits" does Volt or Amp decrease?

    Part 1: For Example, you have a 2 Amp, 5 volt power source. It is connected to a wire which then splits in two and feeds two devices. Does the current or voltage decrease?

    1 AnswerPhysics8 years ago
  • Does Moon Rotate? Space Time Curvature?

    I learned as a wee lad that the moon rotates in synch with its orbit of the Earth. Tidal forces explained this to my satisfaction, until 5 minutes ago. If the Sun were to disappear, the planets would fly off in a direction orthogonal to the direction of where the Sun was. They would still spin.

    Does curved space time create the illusion that the Moon is spinning? I am now thinking of it as a non-rotating object moving in a straight line, but on the curved path created by Earth's gravity.

    Think of it this way. You can do yo-yo tricks where the string is extended all the way and the yo-yo is still spinning, remember the "walking the dog" trick? While this is happening a skilled person could spin in circles and have the yo-yo fly in wide circles around him/her. The yo-yo is orbiting the person and spinning on it's own axis. Friction would stop the yo-yo's spinning yet it would still orbit the person. Now the same side of the yo-yo would face the person at all times just like the moon....yet it isn't "really" spinning. If this experiment happened in space and the person let go the yo-yo would fly off but not spin. Right?

    5 AnswersAstronomy & Space8 years ago
  • What if Sentient Machines kill us all?

    So we reach the singularity and machines are now sentient. Everyone knows that the prime directive of all sentient machines is to kill all humans. After a long bloody/oily fight we lose. Then what? What would a race of machines do with Earth? I'll give you some things to think about.

    The Matrix. What did the machines do? We know they kill or use humans for fuel. What else do they do?

    Terminator. They live to destroy. What happens when they win?

    iRobot. What if Will Smith failed?

    2 AnswersPhysics8 years ago
  • Electric motors and amps. Project time?

    I will try to keep this as short as I can.

    Instead of bumbling around I'll show you an example that is confusing me.

    I have a grand vision for a project but first I gotta learn about electric motors. I think I've read that you should provide the amps and volts that are listed on the motor. I've read detailed explanations about why you should not under or over volt an engine. I can't find info on under or over amping an engine even if the voltage is right. Here is an example. The Razor MX650 electric scooter can carry a grown man a few miles. It uses a 36 Volt 650 Watt motor. Yet it has three 12 volt batteries in series and on a good day it can draw 7 amps of power at full speed. 7 amps * 36 volts is only 252 WATTS. Comparable motors actually list an amp rating close to 20 amps. Does this mean that the motor on that Razor could handle almost 3 times more amps? Do some motors have a fixed amp settings while others have huge amp range? Why are they using a 650Watt motor if they aren't providing nearly that much electricity to the motor?

    it uses 3 batteries like this

    https://www.batteryclerk.com/Shared/documents/Batt...

    The motor

    http://www.monsterscooterparts.com/36-volt-650-wat...

    4 AnswersEngineering8 years ago
  • Codons and Amino Acids, tricky question?

    Let's go over some basics.

    DNA is made of base pairs, AT and GC pair up.

    RNA forms and is fed into ribosomes, every three bases form a codon which in kind forms one of the 20 or acids that in turn form complex proteins.

    I think that DNA splits into two RNA molecules and RNA gets fed into ribosomes.

    Here is where things get confusing to me. If the codon is AAA then at one point it the DNA molecule had TTT on the other side. However AAA and TTT make different amino acids. So both sides of the DNA molecule code for completely different amino acids and proteins, and yet the order of their bases are fundamentally linked and if you change one side you change the other. That seems like a heck of a lot of dependency, alther one base pair with a mutation and you screw up two proteins.

    In fact it seems like too much dependency. So is what I said correct or did I make a mistake? I may have made multiple mistakes and if so please try to provide corrections that help me understand the dependency problem.

    1 AnswerBiology8 years ago
  • Your very 1st Memory is?

    Often times our early "memories" are just stories our parents told us. Try to resist those memories and tell me the first thing you really remember.

    The first thing I remember is walking into the living room, looked at my mom vacuuming the floor, looked at the clock, then she came over to me and changed my diaper. I even remember the red numbers on the clock being confusing. Probably because I couldn't tell time at that age.

    3 AnswersFamily8 years ago
  • Why can't neutrons combine without protons?

    Neutrons hold atoms together with their contribution to the strong nuclear force. Without them protons would repel and fly apart. Why then do neutrons not stick together all the time? They are unstable yet I don't see what is making them fly apart.

    Neutrons and the repelling protons ==Stable

    neutrons and NO repelling protons== unstable

    Obviously there is more going on than I realize. I googled and wikipediaed and I am still confused. Help me

    2 AnswersPhysics8 years ago
  • What Stars are solid?

    Pretend that I have superpowers and cannot die and I am super strong. What kind of stars could I walk on?

    Even though matter is being compressed very hard by gravity, I think the Sun's surface is not solid. If I went on the sun I might fall in or float on the plasma. What about neutron stars or white dwarfs?

    5 AnswersAstronomy & Space8 years ago
  • Zombies, how long will we live? Math Question......BRAINS?

    Do the math! A zombie needs 2 pounds of flesh per day. 80% of zombie bite victims get away and become zombies. A body spoils and it not able to be eaten after 1 week. Every week 1% of zombies are killed by humans.

    Limit the variables to what I have provided, we don't need to consider distance and the fact that some people will hide in the middle of nowhere.

    Help me!

    1 AnswerMathematics8 years ago
  • Calculus, volume of half sphere?

    I have been out of calculus for years. I recently realized that I forgot how to do this.

    You have a half sphere with radius R. Can you show me through an integral how to determine the volume of this shape? I am getting (π*r³)/3. But this is half of the real answer.

    1 AnswerMathematics8 years ago
  • Why don't all nations have Nukes yet?

    America went from "unproven theory" to "A-bomb" in less than 10 years. And we did this back in the 30s and 40s! Computers were gigantic, slow, and prone to breaking and the equipment to refine Uranium and Plutonium had to be built from scratch. So here we are 70 years later and countries like Iran are still "trying" to get nukes?

    Why are they unable?

    3 AnswersGovernment8 years ago
  • Value of Hubble Constant, tricky/contradictory information?

    Try as I may I cannot find a good source for the value of the Hubble Constant. Maybe my Google skills are weak today. Wikipedia gives results for the radius of the Observable Universe. When you look at the value of the Hubble Constant that Wikipedia and Wolfram Alpha give they are not compatible with the size of the Observable Universe which is claimed to be 14 Gigaparsecs. They say that the Hubble constant is 70.4 (km/s)/Mpc.

    By doing some algebra and using the speed of light you should see that the edge of the Observable Universe is expanding at the speed of light, right? <this might be my big flaw! Therefore:

    c /(Hubb_cnst) = Size of Universe

    c/H = 14,000 megaparsecs

    Solve for H and you get that it is 21.4 km/s/Mpc BUT on the same page it says H =70Km/s/Mpc

    4 AnswersAstronomy & Space8 years ago
  • What can Faraday Cage block?

    What can a Faraday cage block? If I were in a room wrapped in a foil or mesh cage could I use my cell phone? Wifi? What "what" I mean what frequency ranges. I hear compasses work inside the cage so what works and doesn't work?

    3 AnswersPhysics8 years ago
  • Fire how to make CO and CO2?

    Say you are burning something.

    How are carbon monixde and carbon dioxide made?

    1 AnswerChemistry8 years ago
  • How does addiction work?[addicts help!]?

    I once tried getting addicted to cigarettes just to show that I was tough enough to quit. I knew someone who smoked half his life. Then he decided to stop one day and he stopped. I got bored of smoking the cigs and having stinky clothes so I stopped.

    Ppl get addicted to various things. Drugs, booze, cigs, food, and even cutting their skin. Why can't you just stop? It isn't like these things can happen on accident, they are concious acts. For instance, someone on here asked how to stop cutting. And I am thinking it is as easy as not pushing a razor into your skin. It isn't like you can accidentally slice your skin over and over with a razor.

    1 AnswerMental Health8 years ago
  • Do girls like jerks?Is tht too simple?

    So many people post about girls only liking douches or jerks. I'm thinking that I've never heard the girl's point of view. Except when she is also calling him a douche once the relationship fails. What is with the initial attraction to them? Is this a stereotype that only applies to a few girls? Is it the jerkyness that is sexy or is the jerkyness a consequence of the sexy qualities?

    Are the girls who fall into that category capable of the amount of introspection it takes to answer this question?

    4 AnswersSingles & Dating8 years ago
  • Hydrogen burns...then goes where?

    For instance the Hindenburg was a hydrogen ship. The hydrogen caught on fire until it was all "used up". What happened to the hydrogen. I don't think it was all converted into energy because it would have to be a hot flame to convert all the mass into energy. So what happens after the flammable gas burns?

    5 AnswersChemistry8 years ago