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About HallsofIvy

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  1. energy transference

    I would think that people huddling together for warmth is an example of "transference of body energy"!
  2. I have difficulties understanding relativity

    You say that as if they don't normally go together!
  3. Help designing a hypothesis or research question

    You've written "an annotated bibliography with tons of sources" on what? How can you research enough to have "tons of sources" if you do not yet know what you are researching?
  4. science is subfield of philosophy

    How old are you?
  5. Help with characteristic equation

    The general solution to the quadratic equation, $ax^2+ bx+ c= 0$ is NOT $\frac{-b}{2a}\pm\sqrt{b^2- 4ac}$. It is $\frac{-b\pm \sqrt{b^2- 4ac}}{2a}$.
  6. What is a vacuum?

    Well, that sort of thing happens with every measurement. If you put a thermometer in a bowl of water to measure its temperature, you change the temperature. When you put an air-gauge on a tire to measure its air pressure, you let some air out so change the air pressure by measuring it.
  7. Time and speed and how speed impacts time

    "pi" is a number and does not change value. I presume what you mean is that in curved space (it doesn't have to be "extreme") the Euclidean relation between circumference and diameter of a circle does not hold so "pi" is irrelevant.
  8. NaCl

    I am confused by your references to "lone pair of electrons". Na, Cl, and H do not have a "pair" of electrons, they have a single valence electron. O has a pair. That is why it requires two H atoms to bond with one O atom to form water, H2O. When NaCl dissociates in water, the Cl ion, Cl- bonds with a H ion, H+ to form the acid HCl, as you say. The Na+ ion bonds with the hydroxide radical, OH-, to form the base NaOH.
  9. Four dimensions (split from The meter-second)

    A "dimension" just means a number used to specify something of interest. If I am marking points on a straight line, then I can designate one of those points, arbitrarily, and designate every point by its distance along that line from that point, using positive and negative to specify "left" or "right" of that point. One number, dimension one. On a plane there are a whole circle of points at a fixed distance from a fixed point so I would also need to specify a direction- two numbers, dimension two. Physicists are interested in "events"- what happens at a specific position at a specific time. It takes three numbers to specify the position and one to specify time. Therefore "four dimensions".
  10. if you were flying on a diagonal and you fell would you fall diagonally?

    An airplane can "fly on a diagonal" because the upward force of air on its wings partially cancels the downward force of gravity to keep it from falling. Once you have fallen out of the airplane, you have only the downward force of gravity- your acceleration is -g. At time t later, your velocity is -gt+ v0 and your position is -(g/2)t^2+ v0t+ x0 where vo is your velocity (velocity of the airplane) at the moment you fell out and x0 is your vector position at that time. You will fall in a parabolic arc with only the initial position and slope or that arc determined by the motion of the airplane.
  11. What has the Earth got to do with Electricity

    Once, when I was young and foolish (I'm not young any more, just foolish) I decided to wire a light fixture myself. Of course, I turned off the electricity to the fixture- at the wall switch. I was very surprised, when I got a shock, to discover that wasn't enough. Now I throw the circuit breaker- or call an electrician.
  12. Topology

    Early in the morning it can be difficult to tell the difference between your coffee cup and your doughnut- but it is very important to avoid pouring hot coffee over yourself! So topology is important.
  13. Expressing fractions as 100% in excel

    Taking the age of the earth as 100% each of these other ages would be divided by the age of the earth, 4.54, then multiplied by 100 to give a percent. For example, the Archean Era would be 3.8/4.54= 0.837 so 83.7%. Proterozoic would be 2.5/4.54= 0.551 so 55.1%. Phanerozoic would be 0.57/4.54= 0.126 so 12.6%.
  14. How gravity works

    1. What do you mean by space-time being "dense"? 2. Since the gravity field of any object extends infinitely, what do you mean by the "edge" of a gravity field?
  15. light

    You titled this "light". Are you referring specifically to light waves rather than "any waves"? Do you know what "polarize" means?